Adding upstream version 13.4.upstream/13.4upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

20 files changed, 14347 insertions, 0 deletions

diff --git a/src/include/nodes/bitmapset.h b/src/include/nodes/bitmapset.h
new file mode 100644
index 0000000..d113c27
--- /dev/null
+++ b/src/include/nodes/bitmapset.h
@@ -0,0 +1,122 @@
+/*-------------------------------------------------------------------------
+ *
+ * bitmapset.h
+ *	  PostgreSQL generic bitmap set package
+ *
+ * A bitmap set can represent any set of nonnegative integers, although
+ * it is mainly intended for sets where the maximum value is not large,
+ * say at most a few hundred.  By convention, a NULL pointer is always
+ * accepted by all operations to represent the empty set.  (But beware
+ * that this is not the only representation of the empty set.  Use
+ * bms_is_empty() in preference to testing for NULL.)
+ *
+ *
+ * Copyright (c) 2003-2020, PostgreSQL Global Development Group
+ *
+ * src/include/nodes/bitmapset.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef BITMAPSET_H
+#define BITMAPSET_H
+
+/*
+ * Forward decl to save including pg_list.h
+ */
+struct List;
+
+/*
+ * Data representation
+ *
+ * Larger bitmap word sizes generally give better performance, so long as
+ * they're not wider than the processor can handle efficiently.  We use
+ * 64-bit words if pointers are that large, else 32-bit words.
+ */
+#if SIZEOF_VOID_P >= 8
+
+#define BITS_PER_BITMAPWORD 64
+typedef uint64 bitmapword;		/* must be an unsigned type */
+typedef int64 signedbitmapword; /* must be the matching signed type */
+
+#else
+
+#define BITS_PER_BITMAPWORD 32
+typedef uint32 bitmapword;		/* must be an unsigned type */
+typedef int32 signedbitmapword; /* must be the matching signed type */
+
+#endif
+
+typedef struct Bitmapset
+{
+	int			nwords;			/* number of words in array */
+	bitmapword	words[FLEXIBLE_ARRAY_MEMBER];	/* really [nwords] */
+} Bitmapset;
+
+
+/* result of bms_subset_compare */
+typedef enum
+{
+	BMS_EQUAL,					/* sets are equal */
+	BMS_SUBSET1,				/* first set is a subset of the second */
+	BMS_SUBSET2,				/* second set is a subset of the first */
+	BMS_DIFFERENT				/* neither set is a subset of the other */
+} BMS_Comparison;
+
+/* result of bms_membership */
+typedef enum
+{
+	BMS_EMPTY_SET,				/* 0 members */
+	BMS_SINGLETON,				/* 1 member */
+	BMS_MULTIPLE				/* >1 member */
+} BMS_Membership;
+
+
+/*
+ * function prototypes in nodes/bitmapset.c
+ */
+
+extern Bitmapset *bms_copy(const Bitmapset *a);
+extern bool bms_equal(const Bitmapset *a, const Bitmapset *b);
+extern int	bms_compare(const Bitmapset *a, const Bitmapset *b);
+extern Bitmapset *bms_make_singleton(int x);
+extern void bms_free(Bitmapset *a);
+
+extern Bitmapset *bms_union(const Bitmapset *a, const Bitmapset *b);
+extern Bitmapset *bms_intersect(const Bitmapset *a, const Bitmapset *b);
+extern Bitmapset *bms_difference(const Bitmapset *a, const Bitmapset *b);
+extern bool bms_is_subset(const Bitmapset *a, const Bitmapset *b);
+extern BMS_Comparison bms_subset_compare(const Bitmapset *a, const Bitmapset *b);
+extern bool bms_is_member(int x, const Bitmapset *a);
+extern int	bms_member_index(Bitmapset *a, int x);
+extern bool bms_overlap(const Bitmapset *a, const Bitmapset *b);
+extern bool bms_overlap_list(const Bitmapset *a, const struct List *b);
+extern bool bms_nonempty_difference(const Bitmapset *a, const Bitmapset *b);
+extern int	bms_singleton_member(const Bitmapset *a);
+extern bool bms_get_singleton_member(const Bitmapset *a, int *member);
+extern int	bms_num_members(const Bitmapset *a);
+
+/* optimized tests when we don't need to know exact membership count: */
+extern BMS_Membership bms_membership(const Bitmapset *a);
+extern bool bms_is_empty(const Bitmapset *a);
+
+/* these routines recycle (modify or free) their non-const inputs: */
+
+extern Bitmapset *bms_add_member(Bitmapset *a, int x);
+extern Bitmapset *bms_del_member(Bitmapset *a, int x);
+extern Bitmapset *bms_add_members(Bitmapset *a, const Bitmapset *b);
+extern Bitmapset *bms_add_range(Bitmapset *a, int lower, int upper);
+extern Bitmapset *bms_int_members(Bitmapset *a, const Bitmapset *b);
+extern Bitmapset *bms_del_members(Bitmapset *a, const Bitmapset *b);
+extern Bitmapset *bms_join(Bitmapset *a, Bitmapset *b);
+
+/* support for iterating through the integer elements of a set: */
+extern int	bms_first_member(Bitmapset *a);
+extern int	bms_next_member(const Bitmapset *a, int prevbit);
+extern int	bms_prev_member(const Bitmapset *a, int prevbit);
+
+/* support for hashtables using Bitmapsets as keys: */
+extern uint32 bms_hash_value(const Bitmapset *a);
+extern uint32 bitmap_hash(const void *key, Size keysize);
+extern int	bitmap_match(const void *key1, const void *key2, Size keysize);
+
+#endif							/* BITMAPSET_H */
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
new file mode 100644
index 0000000..3c6fecd
--- /dev/null
+++ b/src/include/nodes/execnodes.h
@@ -0,0 +1,2523 @@
+/*-------------------------------------------------------------------------
+ *
+ * execnodes.h
+ *	  definitions for executor state nodes
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/execnodes.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef EXECNODES_H
+#define EXECNODES_H
+
+#include "access/tupconvert.h"
+#include "executor/instrument.h"
+#include "fmgr.h"
+#include "lib/pairingheap.h"
+#include "nodes/params.h"
+#include "nodes/plannodes.h"
+#include "nodes/tidbitmap.h"
+#include "partitioning/partdefs.h"
+#include "storage/condition_variable.h"
+#include "utils/hsearch.h"
+#include "utils/queryenvironment.h"
+#include "utils/reltrigger.h"
+#include "utils/sharedtuplestore.h"
+#include "utils/snapshot.h"
+#include "utils/sortsupport.h"
+#include "utils/tuplesort.h"
+#include "utils/tuplestore.h"
+
+struct PlanState;				/* forward references in this file */
+struct PartitionRoutingInfo;
+struct ParallelHashJoinState;
+struct ExecRowMark;
+struct ExprState;
+struct ExprContext;
+struct RangeTblEntry;			/* avoid including parsenodes.h here */
+struct ExprEvalStep;			/* avoid including execExpr.h everywhere */
+struct CopyMultiInsertBuffer;
+
+
+/* ----------------
+ *		ExprState node
+ *
+ * ExprState is the top-level node for expression evaluation.
+ * It contains instructions (in ->steps) to evaluate the expression.
+ * ----------------
+ */
+typedef Datum (*ExprStateEvalFunc) (struct ExprState *expression,
+									struct ExprContext *econtext,
+									bool *isNull);
+
+/* Bits in ExprState->flags (see also execExpr.h for private flag bits): */
+/* expression is for use with ExecQual() */
+#define EEO_FLAG_IS_QUAL					(1 << 0)
+
+typedef struct ExprState
+{
+	NodeTag		tag;
+
+	uint8		flags;			/* bitmask of EEO_FLAG_* bits, see above */
+
+	/*
+	 * Storage for result value of a scalar expression, or for individual
+	 * column results within expressions built by ExecBuildProjectionInfo().
+	 */
+#define FIELDNO_EXPRSTATE_RESNULL 2
+	bool		resnull;
+#define FIELDNO_EXPRSTATE_RESVALUE 3
+	Datum		resvalue;
+
+	/*
+	 * If projecting a tuple result, this slot holds the result; else NULL.
+	 */
+#define FIELDNO_EXPRSTATE_RESULTSLOT 4
+	TupleTableSlot *resultslot;
+
+	/*
+	 * Instructions to compute expression's return value.
+	 */
+	struct ExprEvalStep *steps;
+
+	/*
+	 * Function that actually evaluates the expression.  This can be set to
+	 * different values depending on the complexity of the expression.
+	 */
+	ExprStateEvalFunc evalfunc;
+
+	/* original expression tree, for debugging only */
+	Expr	   *expr;
+
+	/* private state for an evalfunc */
+	void	   *evalfunc_private;
+
+	/*
+	 * XXX: following fields only needed during "compilation" (ExecInitExpr);
+	 * could be thrown away afterwards.
+	 */
+
+	int			steps_len;		/* number of steps currently */
+	int			steps_alloc;	/* allocated length of steps array */
+
+#define FIELDNO_EXPRSTATE_PARENT 11
+	struct PlanState *parent;	/* parent PlanState node, if any */
+	ParamListInfo ext_params;	/* for compiling PARAM_EXTERN nodes */
+
+	Datum	   *innermost_caseval;
+	bool	   *innermost_casenull;
+
+	Datum	   *innermost_domainval;
+	bool	   *innermost_domainnull;
+} ExprState;
+
+
+/* ----------------
+ *	  IndexInfo information
+ *
+ *		this struct holds the information needed to construct new index
+ *		entries for a particular index.  Used for both index_build and
+ *		retail creation of index entries.
+ *
+ *		NumIndexAttrs		total number of columns in this index
+ *		NumIndexKeyAttrs	number of key columns in index
+ *		IndexAttrNumbers	underlying-rel attribute numbers used as keys
+ *							(zeroes indicate expressions). It also contains
+ * 							info about included columns.
+ *		Expressions			expr trees for expression entries, or NIL if none
+ *		ExpressionsState	exec state for expressions, or NIL if none
+ *		Predicate			partial-index predicate, or NIL if none
+ *		PredicateState		exec state for predicate, or NIL if none
+ *		ExclusionOps		Per-column exclusion operators, or NULL if none
+ *		ExclusionProcs		Underlying function OIDs for ExclusionOps
+ *		ExclusionStrats		Opclass strategy numbers for ExclusionOps
+ *		UniqueOps			These are like Exclusion*, but for unique indexes
+ *		UniqueProcs
+ *		UniqueStrats
+ *		Unique				is it a unique index?
+ *		OpclassOptions		opclass-specific options, or NULL if none
+ *		ReadyForInserts		is it valid for inserts?
+ *		Concurrent			are we doing a concurrent index build?
+ *		BrokenHotChain		did we detect any broken HOT chains?
+ *		ParallelWorkers		# of workers requested (excludes leader)
+ *		Am					Oid of index AM
+ *		AmCache				private cache area for index AM
+ *		Context				memory context holding this IndexInfo
+ *
+ * ii_Concurrent, ii_BrokenHotChain, and ii_ParallelWorkers are used only
+ * during index build; they're conventionally zeroed otherwise.
+ * ----------------
+ */
+typedef struct IndexInfo
+{
+	NodeTag		type;
+	int			ii_NumIndexAttrs;	/* total number of columns in index */
+	int			ii_NumIndexKeyAttrs;	/* number of key columns in index */
+	AttrNumber	ii_IndexAttrNumbers[INDEX_MAX_KEYS];
+	List	   *ii_Expressions; /* list of Expr */
+	List	   *ii_ExpressionsState;	/* list of ExprState */
+	List	   *ii_Predicate;	/* list of Expr */
+	ExprState  *ii_PredicateState;
+	Oid		   *ii_ExclusionOps;	/* array with one entry per column */
+	Oid		   *ii_ExclusionProcs;	/* array with one entry per column */
+	uint16	   *ii_ExclusionStrats; /* array with one entry per column */
+	Oid		   *ii_UniqueOps;	/* array with one entry per column */
+	Oid		   *ii_UniqueProcs; /* array with one entry per column */
+	uint16	   *ii_UniqueStrats;	/* array with one entry per column */
+	Datum	   *ii_OpclassOptions;	/* array with one entry per column */
+	bool		ii_Unique;
+	bool		ii_ReadyForInserts;
+	bool		ii_Concurrent;
+	bool		ii_BrokenHotChain;
+	int			ii_ParallelWorkers;
+	Oid			ii_Am;
+	void	   *ii_AmCache;
+	MemoryContext ii_Context;
+} IndexInfo;
+
+/* ----------------
+ *	  ExprContext_CB
+ *
+ *		List of callbacks to be called at ExprContext shutdown.
+ * ----------------
+ */
+typedef void (*ExprContextCallbackFunction) (Datum arg);
+
+typedef struct ExprContext_CB
+{
+	struct ExprContext_CB *next;
+	ExprContextCallbackFunction function;
+	Datum		arg;
+} ExprContext_CB;
+
+/* ----------------
+ *	  ExprContext
+ *
+ *		This class holds the "current context" information
+ *		needed to evaluate expressions for doing tuple qualifications
+ *		and tuple projections.  For example, if an expression refers
+ *		to an attribute in the current inner tuple then we need to know
+ *		what the current inner tuple is and so we look at the expression
+ *		context.
+ *
+ *	There are two memory contexts associated with an ExprContext:
+ *	* ecxt_per_query_memory is a query-lifespan context, typically the same
+ *	  context the ExprContext node itself is allocated in.  This context
+ *	  can be used for purposes such as storing function call cache info.
+ *	* ecxt_per_tuple_memory is a short-term context for expression results.
+ *	  As the name suggests, it will typically be reset once per tuple,
+ *	  before we begin to evaluate expressions for that tuple.  Each
+ *	  ExprContext normally has its very own per-tuple memory context.
+ *
+ *	CurrentMemoryContext should be set to ecxt_per_tuple_memory before
+ *	calling ExecEvalExpr() --- see ExecEvalExprSwitchContext().
+ * ----------------
+ */
+typedef struct ExprContext
+{
+	NodeTag		type;
+
+	/* Tuples that Var nodes in expression may refer to */
+#define FIELDNO_EXPRCONTEXT_SCANTUPLE 1
+	TupleTableSlot *ecxt_scantuple;
+#define FIELDNO_EXPRCONTEXT_INNERTUPLE 2
+	TupleTableSlot *ecxt_innertuple;
+#define FIELDNO_EXPRCONTEXT_OUTERTUPLE 3
+	TupleTableSlot *ecxt_outertuple;
+
+	/* Memory contexts for expression evaluation --- see notes above */
+	MemoryContext ecxt_per_query_memory;
+	MemoryContext ecxt_per_tuple_memory;
+
+	/* Values to substitute for Param nodes in expression */
+	ParamExecData *ecxt_param_exec_vals;	/* for PARAM_EXEC params */
+	ParamListInfo ecxt_param_list_info; /* for other param types */
+
+	/*
+	 * Values to substitute for Aggref nodes in the expressions of an Agg
+	 * node, or for WindowFunc nodes within a WindowAgg node.
+	 */
+#define FIELDNO_EXPRCONTEXT_AGGVALUES 8
+	Datum	   *ecxt_aggvalues; /* precomputed values for aggs/windowfuncs */
+#define FIELDNO_EXPRCONTEXT_AGGNULLS 9
+	bool	   *ecxt_aggnulls;	/* null flags for aggs/windowfuncs */
+
+	/* Value to substitute for CaseTestExpr nodes in expression */
+#define FIELDNO_EXPRCONTEXT_CASEDATUM 10
+	Datum		caseValue_datum;
+#define FIELDNO_EXPRCONTEXT_CASENULL 11
+	bool		caseValue_isNull;
+
+	/* Value to substitute for CoerceToDomainValue nodes in expression */
+#define FIELDNO_EXPRCONTEXT_DOMAINDATUM 12
+	Datum		domainValue_datum;
+#define FIELDNO_EXPRCONTEXT_DOMAINNULL 13
+	bool		domainValue_isNull;
+
+	/* Link to containing EState (NULL if a standalone ExprContext) */
+	struct EState *ecxt_estate;
+
+	/* Functions to call back when ExprContext is shut down or rescanned */
+	ExprContext_CB *ecxt_callbacks;
+} ExprContext;
+
+/*
+ * Set-result status used when evaluating functions potentially returning a
+ * set.
+ */
+typedef enum
+{
+	ExprSingleResult,			/* expression does not return a set */
+	ExprMultipleResult,			/* this result is an element of a set */
+	ExprEndResult				/* there are no more elements in the set */
+} ExprDoneCond;
+
+/*
+ * Return modes for functions returning sets.  Note values must be chosen
+ * as separate bits so that a bitmask can be formed to indicate supported
+ * modes.  SFRM_Materialize_Random and SFRM_Materialize_Preferred are
+ * auxiliary flags about SFRM_Materialize mode, rather than separate modes.
+ */
+typedef enum
+{
+	SFRM_ValuePerCall = 0x01,	/* one value returned per call */
+	SFRM_Materialize = 0x02,	/* result set instantiated in Tuplestore */
+	SFRM_Materialize_Random = 0x04, /* Tuplestore needs randomAccess */
+	SFRM_Materialize_Preferred = 0x08	/* caller prefers Tuplestore */
+} SetFunctionReturnMode;
+
+/*
+ * When calling a function that might return a set (multiple rows),
+ * a node of this type is passed as fcinfo->resultinfo to allow
+ * return status to be passed back.  A function returning set should
+ * raise an error if no such resultinfo is provided.
+ */
+typedef struct ReturnSetInfo
+{
+	NodeTag		type;
+	/* values set by caller: */
+	ExprContext *econtext;		/* context function is being called in */
+	TupleDesc	expectedDesc;	/* tuple descriptor expected by caller */
+	int			allowedModes;	/* bitmask: return modes caller can handle */
+	/* result status from function (but pre-initialized by caller): */
+	SetFunctionReturnMode returnMode;	/* actual return mode */
+	ExprDoneCond isDone;		/* status for ValuePerCall mode */
+	/* fields filled by function in Materialize return mode: */
+	Tuplestorestate *setResult; /* holds the complete returned tuple set */
+	TupleDesc	setDesc;		/* actual descriptor for returned tuples */
+} ReturnSetInfo;
+
+/* ----------------
+ *		ProjectionInfo node information
+ *
+ *		This is all the information needed to perform projections ---
+ *		that is, form new tuples by evaluation of targetlist expressions.
+ *		Nodes which need to do projections create one of these.
+ *
+ *		The target tuple slot is kept in ProjectionInfo->pi_state.resultslot.
+ *		ExecProject() evaluates the tlist, forms a tuple, and stores it
+ *		in the given slot.  Note that the result will be a "virtual" tuple
+ *		unless ExecMaterializeSlot() is then called to force it to be
+ *		converted to a physical tuple.  The slot must have a tupledesc
+ *		that matches the output of the tlist!
+ * ----------------
+ */
+typedef struct ProjectionInfo
+{
+	NodeTag		type;
+	/* instructions to evaluate projection */
+	ExprState	pi_state;
+	/* expression context in which to evaluate expression */
+	ExprContext *pi_exprContext;
+} ProjectionInfo;
+
+/* ----------------
+ *	  JunkFilter
+ *
+ *	  This class is used to store information regarding junk attributes.
+ *	  A junk attribute is an attribute in a tuple that is needed only for
+ *	  storing intermediate information in the executor, and does not belong
+ *	  in emitted tuples.  For example, when we do an UPDATE query,
+ *	  the planner adds a "junk" entry to the targetlist so that the tuples
+ *	  returned to ExecutePlan() contain an extra attribute: the ctid of
+ *	  the tuple to be updated.  This is needed to do the update, but we
+ *	  don't want the ctid to be part of the stored new tuple!  So, we
+ *	  apply a "junk filter" to remove the junk attributes and form the
+ *	  real output tuple.  The junkfilter code also provides routines to
+ *	  extract the values of the junk attribute(s) from the input tuple.
+ *
+ *	  targetList:		the original target list (including junk attributes).
+ *	  cleanTupType:		the tuple descriptor for the "clean" tuple (with
+ *						junk attributes removed).
+ *	  cleanMap:			A map with the correspondence between the non-junk
+ *						attribute numbers of the "original" tuple and the
+ *						attribute numbers of the "clean" tuple.
+ *	  resultSlot:		tuple slot used to hold cleaned tuple.
+ *	  junkAttNo:		not used by junkfilter code.  Can be used by caller
+ *						to remember the attno of a specific junk attribute
+ *						(nodeModifyTable.c keeps the "ctid" or "wholerow"
+ *						attno here).
+ * ----------------
+ */
+typedef struct JunkFilter
+{
+	NodeTag		type;
+	List	   *jf_targetList;
+	TupleDesc	jf_cleanTupType;
+	AttrNumber *jf_cleanMap;
+	TupleTableSlot *jf_resultSlot;
+	AttrNumber	jf_junkAttNo;
+} JunkFilter;
+
+/*
+ * OnConflictSetState
+ *
+ * Executor state of an ON CONFLICT DO UPDATE operation.
+ */
+typedef struct OnConflictSetState
+{
+	NodeTag		type;
+
+	TupleTableSlot *oc_Existing;	/* slot to store existing target tuple in */
+	TupleTableSlot *oc_ProjSlot;	/* CONFLICT ... SET ... projection target */
+	ProjectionInfo *oc_ProjInfo;	/* for ON CONFLICT DO UPDATE SET */
+	ExprState  *oc_WhereClause; /* state for the WHERE clause */
+} OnConflictSetState;
+
+/*
+ * ResultRelInfo
+ *
+ * Whenever we update an existing relation, we have to update indexes on the
+ * relation, and perhaps also fire triggers.  ResultRelInfo holds all the
+ * information needed about a result relation, including indexes.
+ *
+ * Normally, a ResultRelInfo refers to a table that is in the query's range
+ * table; then ri_RangeTableIndex is the RT index and ri_RelationDesc is
+ * just a copy of the relevant es_relations[] entry.  However, in some
+ * situations we create ResultRelInfos for relations that are not in the
+ * range table, namely for targets of tuple routing in a partitioned table,
+ * and when firing triggers in tables other than the target tables (See
+ * ExecGetTriggerResultRel).  In these situations, ri_RangeTableIndex is 0
+ * and ri_RelationDesc is a separately-opened relcache pointer that needs to
+ * be separately closed.
+ */
+typedef struct ResultRelInfo
+{
+	NodeTag		type;
+
+	/* result relation's range table index, or 0 if not in range table */
+	Index		ri_RangeTableIndex;
+
+	/* relation descriptor for result relation */
+	Relation	ri_RelationDesc;
+
+	/* # of indices existing on result relation */
+	int			ri_NumIndices;
+
+	/* array of relation descriptors for indices */
+	RelationPtr ri_IndexRelationDescs;
+
+	/* array of key/attr info for indices */
+	IndexInfo **ri_IndexRelationInfo;
+
+	/* triggers to be fired, if any */
+	TriggerDesc *ri_TrigDesc;
+
+	/* cached lookup info for trigger functions */
+	FmgrInfo   *ri_TrigFunctions;
+
+	/* array of trigger WHEN expr states */
+	ExprState **ri_TrigWhenExprs;
+
+	/* optional runtime measurements for triggers */
+	Instrumentation *ri_TrigInstrument;
+
+	/* On-demand created slots for triggers / returning processing */
+	TupleTableSlot *ri_ReturningSlot;	/* for trigger output tuples */
+	TupleTableSlot *ri_TrigOldSlot; /* for a trigger's old tuple */
+	TupleTableSlot *ri_TrigNewSlot; /* for a trigger's new tuple */
+
+	/* FDW callback functions, if foreign table */
+	struct FdwRoutine *ri_FdwRoutine;
+
+	/* available to save private state of FDW */
+	void	   *ri_FdwState;
+
+	/* true when modifying foreign table directly */
+	bool		ri_usesFdwDirectModify;
+
+	/* list of WithCheckOption's to be checked */
+	List	   *ri_WithCheckOptions;
+
+	/* list of WithCheckOption expr states */
+	List	   *ri_WithCheckOptionExprs;
+
+	/* array of constraint-checking expr states */
+	ExprState **ri_ConstraintExprs;
+
+	/* array of stored generated columns expr states */
+	ExprState **ri_GeneratedExprs;
+
+	/* number of stored generated columns we need to compute */
+	int			ri_NumGeneratedNeeded;
+
+	/* for removing junk attributes from tuples */
+	JunkFilter *ri_junkFilter;
+
+	/* list of RETURNING expressions */
+	List	   *ri_returningList;
+
+	/* for computing a RETURNING list */
+	ProjectionInfo *ri_projectReturning;
+
+	/* list of arbiter indexes to use to check conflicts */
+	List	   *ri_onConflictArbiterIndexes;
+
+	/* ON CONFLICT evaluation state */
+	OnConflictSetState *ri_onConflict;
+
+	/* partition check expression */
+	List	   *ri_PartitionCheck;
+
+	/* partition check expression state */
+	ExprState  *ri_PartitionCheckExpr;
+
+	/*
+	 * RootResultRelInfo gives the target relation mentioned in the query, if
+	 * it's a partitioned table. It is not set if the target relation
+	 * mentioned in the query is an inherited table, nor when tuple routing is
+	 * not needed.
+	 */
+	struct ResultRelInfo *ri_RootResultRelInfo;
+
+	/* Additional information specific to partition tuple routing */
+	struct PartitionRoutingInfo *ri_PartitionInfo;
+
+	/* For use by copy.c when performing multi-inserts */
+	struct CopyMultiInsertBuffer *ri_CopyMultiInsertBuffer;
+} ResultRelInfo;
+
+/* ----------------
+ *	  EState information
+ *
+ * Master working state for an Executor invocation
+ * ----------------
+ */
+typedef struct EState
+{
+	NodeTag		type;
+
+	/* Basic state for all query types: */
+	ScanDirection es_direction; /* current scan direction */
+	Snapshot	es_snapshot;	/* time qual to use */
+	Snapshot	es_crosscheck_snapshot; /* crosscheck time qual for RI */
+	List	   *es_range_table; /* List of RangeTblEntry */
+	Index		es_range_table_size;	/* size of the range table arrays */
+	Relation   *es_relations;	/* Array of per-range-table-entry Relation
+								 * pointers, or NULL if not yet opened */
+	struct ExecRowMark **es_rowmarks;	/* Array of per-range-table-entry
+										 * ExecRowMarks, or NULL if none */
+	PlannedStmt *es_plannedstmt;	/* link to top of plan tree */
+	const char *es_sourceText;	/* Source text from QueryDesc */
+
+	JunkFilter *es_junkFilter;	/* top-level junk filter, if any */
+
+	/* If query can insert/delete tuples, the command ID to mark them with */
+	CommandId	es_output_cid;
+
+	/* Info about target table(s) for insert/update/delete queries: */
+	ResultRelInfo *es_result_relations; /* array of ResultRelInfos */
+	int			es_num_result_relations;	/* length of array */
+	ResultRelInfo *es_result_relation_info; /* currently active array elt */
+
+	/*
+	 * Info about the partition root table(s) for insert/update/delete queries
+	 * targeting partitioned tables.  Only leaf partitions are mentioned in
+	 * es_result_relations, but we need access to the roots for firing
+	 * triggers and for runtime tuple routing.
+	 */
+	ResultRelInfo *es_root_result_relations;	/* array of ResultRelInfos */
+	int			es_num_root_result_relations;	/* length of the array */
+	PartitionDirectory es_partition_directory;	/* for PartitionDesc lookup */
+
+	/*
+	 * The following list contains ResultRelInfos created by the tuple routing
+	 * code for partitions that don't already have one.
+	 */
+	List	   *es_tuple_routing_result_relations;
+
+	/* Stuff used for firing triggers: */
+	List	   *es_trig_target_relations;	/* trigger-only ResultRelInfos */
+
+	/* Parameter info: */
+	ParamListInfo es_param_list_info;	/* values of external params */
+	ParamExecData *es_param_exec_vals;	/* values of internal params */
+
+	QueryEnvironment *es_queryEnv;	/* query environment */
+
+	/* Other working state: */
+	MemoryContext es_query_cxt; /* per-query context in which EState lives */
+
+	List	   *es_tupleTable;	/* List of TupleTableSlots */
+
+	uint64		es_processed;	/* # of tuples processed */
+
+	int			es_top_eflags;	/* eflags passed to ExecutorStart */
+	int			es_instrument;	/* OR of InstrumentOption flags */
+	bool		es_finished;	/* true when ExecutorFinish is done */
+
+	List	   *es_exprcontexts;	/* List of ExprContexts within EState */
+
+	List	   *es_subplanstates;	/* List of PlanState for SubPlans */
+
+	List	   *es_auxmodifytables; /* List of secondary ModifyTableStates */
+
+	/*
+	 * this ExprContext is for per-output-tuple operations, such as constraint
+	 * checks and index-value computations.  It will be reset for each output
+	 * tuple.  Note that it will be created only if needed.
+	 */
+	ExprContext *es_per_tuple_exprcontext;
+
+	/*
+	 * If not NULL, this is an EPQState's EState. This is a field in EState
+	 * both to allow EvalPlanQual aware executor nodes to detect that they
+	 * need to perform EPQ related work, and to provide necessary information
+	 * to do so.
+	 */
+	struct EPQState *es_epq_active;
+
+	bool		es_use_parallel_mode;	/* can we use parallel workers? */
+
+	/* The per-query shared memory area to use for parallel execution. */
+	struct dsa_area *es_query_dsa;
+
+	/*
+	 * JIT information. es_jit_flags indicates whether JIT should be performed
+	 * and with which options.  es_jit is created on-demand when JITing is
+	 * performed.
+	 *
+	 * es_jit_worker_instr is the combined, on demand allocated,
+	 * instrumentation from all workers. The leader's instrumentation is kept
+	 * separate, and is combined on demand by ExplainPrintJITSummary().
+	 */
+	int			es_jit_flags;
+	struct JitContext *es_jit;
+	struct JitInstrumentation *es_jit_worker_instr;
+} EState;
+
+
+/*
+ * ExecRowMark -
+ *	   runtime representation of FOR [KEY] UPDATE/SHARE clauses
+ *
+ * When doing UPDATE, DELETE, or SELECT FOR [KEY] UPDATE/SHARE, we will have an
+ * ExecRowMark for each non-target relation in the query (except inheritance
+ * parent RTEs, which can be ignored at runtime).  Virtual relations such as
+ * subqueries-in-FROM will have an ExecRowMark with relation == NULL.  See
+ * PlanRowMark for details about most of the fields.  In addition to fields
+ * directly derived from PlanRowMark, we store an activity flag (to denote
+ * inactive children of inheritance trees), curCtid, which is used by the
+ * WHERE CURRENT OF code, and ermExtra, which is available for use by the plan
+ * node that sources the relation (e.g., for a foreign table the FDW can use
+ * ermExtra to hold information).
+ *
+ * EState->es_rowmarks is an array of these structs, indexed by RT index,
+ * with NULLs for irrelevant RT indexes.  es_rowmarks itself is NULL if
+ * there are no rowmarks.
+ */
+typedef struct ExecRowMark
+{
+	Relation	relation;		/* opened and suitably locked relation */
+	Oid			relid;			/* its OID (or InvalidOid, if subquery) */
+	Index		rti;			/* its range table index */
+	Index		prti;			/* parent range table index, if child */
+	Index		rowmarkId;		/* unique identifier for resjunk columns */
+	RowMarkType markType;		/* see enum in nodes/plannodes.h */
+	LockClauseStrength strength;	/* LockingClause's strength, or LCS_NONE */
+	LockWaitPolicy waitPolicy;	/* NOWAIT and SKIP LOCKED */
+	bool		ermActive;		/* is this mark relevant for current tuple? */
+	ItemPointerData curCtid;	/* ctid of currently locked tuple, if any */
+	void	   *ermExtra;		/* available for use by relation source node */
+} ExecRowMark;
+
+/*
+ * ExecAuxRowMark -
+ *	   additional runtime representation of FOR [KEY] UPDATE/SHARE clauses
+ *
+ * Each LockRows and ModifyTable node keeps a list of the rowmarks it needs to
+ * deal with.  In addition to a pointer to the related entry in es_rowmarks,
+ * this struct carries the column number(s) of the resjunk columns associated
+ * with the rowmark (see comments for PlanRowMark for more detail).  In the
+ * case of ModifyTable, there has to be a separate ExecAuxRowMark list for
+ * each child plan, because the resjunk columns could be at different physical
+ * column positions in different subplans.
+ */
+typedef struct ExecAuxRowMark
+{
+	ExecRowMark *rowmark;		/* related entry in es_rowmarks */
+	AttrNumber	ctidAttNo;		/* resno of ctid junk attribute, if any */
+	AttrNumber	toidAttNo;		/* resno of tableoid junk attribute, if any */
+	AttrNumber	wholeAttNo;		/* resno of whole-row junk attribute, if any */
+} ExecAuxRowMark;
+
+
+/* ----------------------------------------------------------------
+ *				 Tuple Hash Tables
+ *
+ * All-in-memory tuple hash tables are used for a number of purposes.
+ *
+ * Note: tab_hash_funcs are for the key datatype(s) stored in the table,
+ * and tab_eq_funcs are non-cross-type equality operators for those types.
+ * Normally these are the only functions used, but FindTupleHashEntry()
+ * supports searching a hashtable using cross-data-type hashing.  For that,
+ * the caller must supply hash functions for the LHS datatype as well as
+ * the cross-type equality operators to use.  in_hash_funcs and cur_eq_func
+ * are set to point to the caller's function arrays while doing such a search.
+ * During LookupTupleHashEntry(), they point to tab_hash_funcs and
+ * tab_eq_func respectively.
+ * ----------------------------------------------------------------
+ */
+typedef struct TupleHashEntryData *TupleHashEntry;
+typedef struct TupleHashTableData *TupleHashTable;
+
+typedef struct TupleHashEntryData
+{
+	MinimalTuple firstTuple;	/* copy of first tuple in this group */
+	void	   *additional;		/* user data */
+	uint32		status;			/* hash status */
+	uint32		hash;			/* hash value (cached) */
+} TupleHashEntryData;
+
+/* define parameters necessary to generate the tuple hash table interface */
+#define SH_PREFIX tuplehash
+#define SH_ELEMENT_TYPE TupleHashEntryData
+#define SH_KEY_TYPE MinimalTuple
+#define SH_SCOPE extern
+#define SH_DECLARE
+#include "lib/simplehash.h"
+
+typedef struct TupleHashTableData
+{
+	tuplehash_hash *hashtab;	/* underlying hash table */
+	int			numCols;		/* number of columns in lookup key */
+	AttrNumber *keyColIdx;		/* attr numbers of key columns */
+	FmgrInfo   *tab_hash_funcs; /* hash functions for table datatype(s) */
+	ExprState  *tab_eq_func;	/* comparator for table datatype(s) */
+	Oid		   *tab_collations; /* collations for hash and comparison */
+	MemoryContext tablecxt;		/* memory context containing table */
+	MemoryContext tempcxt;		/* context for function evaluations */
+	Size		entrysize;		/* actual size to make each hash entry */
+	TupleTableSlot *tableslot;	/* slot for referencing table entries */
+	/* The following fields are set transiently for each table search: */
+	TupleTableSlot *inputslot;	/* current input tuple's slot */
+	FmgrInfo   *in_hash_funcs;	/* hash functions for input datatype(s) */
+	ExprState  *cur_eq_func;	/* comparator for input vs. table */
+	uint32		hash_iv;		/* hash-function IV */
+	ExprContext *exprcontext;	/* expression context */
+}			TupleHashTableData;
+
+typedef tuplehash_iterator TupleHashIterator;
+
+/*
+ * Use InitTupleHashIterator/TermTupleHashIterator for a read/write scan.
+ * Use ResetTupleHashIterator if the table can be frozen (in this case no
+ * explicit scan termination is needed).
+ */
+#define InitTupleHashIterator(htable, iter) \
+	tuplehash_start_iterate(htable->hashtab, iter)
+#define TermTupleHashIterator(iter) \
+	((void) 0)
+#define ResetTupleHashIterator(htable, iter) \
+	InitTupleHashIterator(htable, iter)
+#define ScanTupleHashTable(htable, iter) \
+	tuplehash_iterate(htable->hashtab, iter)
+
+
+/* ----------------------------------------------------------------
+ *				 Expression State Nodes
+ *
+ * Formerly, there was a separate executor expression state node corresponding
+ * to each node in a planned expression tree.  That's no longer the case; for
+ * common expression node types, all the execution info is embedded into
+ * step(s) in a single ExprState node.  But we still have a few executor state
+ * node types for selected expression node types, mostly those in which info
+ * has to be shared with other parts of the execution state tree.
+ * ----------------------------------------------------------------
+ */
+
+/* ----------------
+ *		AggrefExprState node
+ * ----------------
+ */
+typedef struct AggrefExprState
+{
+	NodeTag		type;
+	Aggref	   *aggref;			/* expression plan node */
+	int			aggno;			/* ID number for agg within its plan node */
+} AggrefExprState;
+
+/* ----------------
+ *		WindowFuncExprState node
+ * ----------------
+ */
+typedef struct WindowFuncExprState
+{
+	NodeTag		type;
+	WindowFunc *wfunc;			/* expression plan node */
+	List	   *args;			/* ExprStates for argument expressions */
+	ExprState  *aggfilter;		/* FILTER expression */
+	int			wfuncno;		/* ID number for wfunc within its plan node */
+} WindowFuncExprState;
+
+
+/* ----------------
+ *		SetExprState node
+ *
+ * State for evaluating a potentially set-returning expression (like FuncExpr
+ * or OpExpr).  In some cases, like some of the expressions in ROWS FROM(...)
+ * the expression might not be a SRF, but nonetheless it uses the same
+ * machinery as SRFs; it will be treated as a SRF returning a single row.
+ * ----------------
+ */
+typedef struct SetExprState
+{
+	NodeTag		type;
+	Expr	   *expr;			/* expression plan node */
+	List	   *args;			/* ExprStates for argument expressions */
+
+	/*
+	 * In ROWS FROM, functions can be inlined, removing the FuncExpr normally
+	 * inside.  In such a case this is the compiled expression (which cannot
+	 * return a set), which'll be evaluated using regular ExecEvalExpr().
+	 */
+	ExprState  *elidedFuncState;
+
+	/*
+	 * Function manager's lookup info for the target function.  If func.fn_oid
+	 * is InvalidOid, we haven't initialized it yet (nor any of the following
+	 * fields, except funcReturnsSet).
+	 */
+	FmgrInfo	func;
+
+	/*
+	 * For a set-returning function (SRF) that returns a tuplestore, we keep
+	 * the tuplestore here and dole out the result rows one at a time. The
+	 * slot holds the row currently being returned.
+	 */
+	Tuplestorestate *funcResultStore;
+	TupleTableSlot *funcResultSlot;
+
+	/*
+	 * In some cases we need to compute a tuple descriptor for the function's
+	 * output.  If so, it's stored here.
+	 */
+	TupleDesc	funcResultDesc;
+	bool		funcReturnsTuple;	/* valid when funcResultDesc isn't NULL */
+
+	/*
+	 * Remember whether the function is declared to return a set.  This is set
+	 * by ExecInitExpr, and is valid even before the FmgrInfo is set up.
+	 */
+	bool		funcReturnsSet;
+
+	/*
+	 * setArgsValid is true when we are evaluating a set-returning function
+	 * that uses value-per-call mode and we are in the middle of a call
+	 * series; we want to pass the same argument values to the function again
+	 * (and again, until it returns ExprEndResult).  This indicates that
+	 * fcinfo_data already contains valid argument data.
+	 */
+	bool		setArgsValid;
+
+	/*
+	 * Flag to remember whether we have registered a shutdown callback for
+	 * this SetExprState.  We do so only if funcResultStore or setArgsValid
+	 * has been set at least once (since all the callback is for is to release
+	 * the tuplestore or clear setArgsValid).
+	 */
+	bool		shutdown_reg;	/* a shutdown callback is registered */
+
+	/*
+	 * Call parameter structure for the function.  This has been initialized
+	 * (by InitFunctionCallInfoData) if func.fn_oid is valid.  It also saves
+	 * argument values between calls, when setArgsValid is true.
+	 */
+	FunctionCallInfo fcinfo;
+} SetExprState;
+
+/* ----------------
+ *		SubPlanState node
+ * ----------------
+ */
+typedef struct SubPlanState
+{
+	NodeTag		type;
+	SubPlan    *subplan;		/* expression plan node */
+	struct PlanState *planstate;	/* subselect plan's state tree */
+	struct PlanState *parent;	/* parent plan node's state tree */
+	ExprState  *testexpr;		/* state of combining expression */
+	List	   *args;			/* states of argument expression(s) */
+	HeapTuple	curTuple;		/* copy of most recent tuple from subplan */
+	Datum		curArray;		/* most recent array from ARRAY() subplan */
+	/* these are used when hashing the subselect's output: */
+	TupleDesc	descRight;		/* subselect desc after projection */
+	ProjectionInfo *projLeft;	/* for projecting lefthand exprs */
+	ProjectionInfo *projRight;	/* for projecting subselect output */
+	TupleHashTable hashtable;	/* hash table for no-nulls subselect rows */
+	TupleHashTable hashnulls;	/* hash table for rows with null(s) */
+	bool		havehashrows;	/* true if hashtable is not empty */
+	bool		havenullrows;	/* true if hashnulls is not empty */
+	MemoryContext hashtablecxt; /* memory context containing hash tables */
+	MemoryContext hashtempcxt;	/* temp memory context for hash tables */
+	ExprContext *innerecontext; /* econtext for computing inner tuples */
+	int			numCols;		/* number of columns being hashed */
+	/* each of the remaining fields is an array of length numCols: */
+	AttrNumber *keyColIdx;		/* control data for hash tables */
+	Oid		   *tab_eq_funcoids;	/* equality func oids for table
+									 * datatype(s) */
+	Oid		   *tab_collations; /* collations for hash and comparison */
+	FmgrInfo   *tab_hash_funcs; /* hash functions for table datatype(s) */
+	FmgrInfo   *tab_eq_funcs;	/* equality functions for table datatype(s) */
+	FmgrInfo   *lhs_hash_funcs; /* hash functions for lefthand datatype(s) */
+	FmgrInfo   *cur_eq_funcs;	/* equality functions for LHS vs. table */
+	ExprState  *cur_eq_comp;	/* equality comparator for LHS vs. table */
+} SubPlanState;
+
+/* ----------------
+ *		AlternativeSubPlanState node
+ * ----------------
+ */
+typedef struct AlternativeSubPlanState
+{
+	NodeTag		type;
+	AlternativeSubPlan *subplan;	/* expression plan node */
+	List	   *subplans;		/* SubPlanStates of alternative subplans */
+	int			active;			/* list index of the one we're using */
+} AlternativeSubPlanState;
+
+/*
+ * DomainConstraintState - one item to check during CoerceToDomain
+ *
+ * Note: we consider this to be part of an ExprState tree, so we give it
+ * a name following the xxxState convention.  But there's no directly
+ * associated plan-tree node.
+ */
+typedef enum DomainConstraintType
+{
+	DOM_CONSTRAINT_NOTNULL,
+	DOM_CONSTRAINT_CHECK
+} DomainConstraintType;
+
+typedef struct DomainConstraintState
+{
+	NodeTag		type;
+	DomainConstraintType constrainttype;	/* constraint type */
+	char	   *name;			/* name of constraint (for error msgs) */
+	Expr	   *check_expr;		/* for CHECK, a boolean expression */
+	ExprState  *check_exprstate;	/* check_expr's eval state, or NULL */
+} DomainConstraintState;
+
+
+/* ----------------------------------------------------------------
+ *				 Executor State Trees
+ *
+ * An executing query has a PlanState tree paralleling the Plan tree
+ * that describes the plan.
+ * ----------------------------------------------------------------
+ */
+
+/* ----------------
+ *	 ExecProcNodeMtd
+ *
+ * This is the method called by ExecProcNode to return the next tuple
+ * from an executor node.  It returns NULL, or an empty TupleTableSlot,
+ * if no more tuples are available.
+ * ----------------
+ */
+typedef TupleTableSlot *(*ExecProcNodeMtd) (struct PlanState *pstate);
+
+/* ----------------
+ *		PlanState node
+ *
+ * We never actually instantiate any PlanState nodes; this is just the common
+ * abstract superclass for all PlanState-type nodes.
+ * ----------------
+ */
+typedef struct PlanState
+{
+	NodeTag		type;
+
+	Plan	   *plan;			/* associated Plan node */
+
+	EState	   *state;			/* at execution time, states of individual
+								 * nodes point to one EState for the whole
+								 * top-level plan */
+
+	ExecProcNodeMtd ExecProcNode;	/* function to return next tuple */
+	ExecProcNodeMtd ExecProcNodeReal;	/* actual function, if above is a
+										 * wrapper */
+
+	Instrumentation *instrument;	/* Optional runtime stats for this node */
+	WorkerInstrumentation *worker_instrument;	/* per-worker instrumentation */
+
+	/* Per-worker JIT instrumentation */
+	struct SharedJitInstrumentation *worker_jit_instrument;
+
+	/*
+	 * Common structural data for all Plan types.  These links to subsidiary
+	 * state trees parallel links in the associated plan tree (except for the
+	 * subPlan list, which does not exist in the plan tree).
+	 */
+	ExprState  *qual;			/* boolean qual condition */
+	struct PlanState *lefttree; /* input plan tree(s) */
+	struct PlanState *righttree;
+
+	List	   *initPlan;		/* Init SubPlanState nodes (un-correlated expr
+								 * subselects) */
+	List	   *subPlan;		/* SubPlanState nodes in my expressions */
+
+	/*
+	 * State for management of parameter-change-driven rescanning
+	 */
+	Bitmapset  *chgParam;		/* set of IDs of changed Params */
+
+	/*
+	 * Other run-time state needed by most if not all node types.
+	 */
+	TupleDesc	ps_ResultTupleDesc; /* node's return type */
+	TupleTableSlot *ps_ResultTupleSlot; /* slot for my result tuples */
+	ExprContext *ps_ExprContext;	/* node's expression-evaluation context */
+	ProjectionInfo *ps_ProjInfo;	/* info for doing tuple projection */
+
+	/*
+	 * Scanslot's descriptor if known. This is a bit of a hack, but otherwise
+	 * it's hard for expression compilation to optimize based on the
+	 * descriptor, without encoding knowledge about all executor nodes.
+	 */
+	TupleDesc	scandesc;
+
+	/*
+	 * Define the slot types for inner, outer and scanslots for expression
+	 * contexts with this state as a parent.  If *opsset is set, then
+	 * *opsfixed indicates whether *ops is guaranteed to be the type of slot
+	 * used. That means that every slot in the corresponding
+	 * ExprContext.ecxt_*tuple will point to a slot of that type, while
+	 * evaluating the expression.  If *opsfixed is false, but *ops is set,
+	 * that indicates the most likely type of slot.
+	 *
+	 * The scan* fields are set by ExecInitScanTupleSlot(). If that's not
+	 * called, nodes can initialize the fields themselves.
+	 *
+	 * If outer/inneropsset is false, the information is inferred on-demand
+	 * using ExecGetResultSlotOps() on ->righttree/lefttree, using the
+	 * corresponding node's resultops* fields.
+	 *
+	 * The result* fields are automatically set when ExecInitResultSlot is
+	 * used (be it directly or when the slot is created by
+	 * ExecAssignScanProjectionInfo() /
+	 * ExecConditionalAssignProjectionInfo()).  If no projection is necessary
+	 * ExecConditionalAssignProjectionInfo() defaults those fields to the scan
+	 * operations.
+	 */
+	const TupleTableSlotOps *scanops;
+	const TupleTableSlotOps *outerops;
+	const TupleTableSlotOps *innerops;
+	const TupleTableSlotOps *resultops;
+	bool		scanopsfixed;
+	bool		outeropsfixed;
+	bool		inneropsfixed;
+	bool		resultopsfixed;
+	bool		scanopsset;
+	bool		outeropsset;
+	bool		inneropsset;
+	bool		resultopsset;
+} PlanState;
+
+/* ----------------
+ *	these are defined to avoid confusion problems with "left"
+ *	and "right" and "inner" and "outer".  The convention is that
+ *	the "left" plan is the "outer" plan and the "right" plan is
+ *	the inner plan, but these make the code more readable.
+ * ----------------
+ */
+#define innerPlanState(node)		(((PlanState *)(node))->righttree)
+#define outerPlanState(node)		(((PlanState *)(node))->lefttree)
+
+/* Macros for inline access to certain instrumentation counters */
+#define InstrCountTuples2(node, delta) \
+	do { \
+		if (((PlanState *)(node))->instrument) \
+			((PlanState *)(node))->instrument->ntuples2 += (delta); \
+	} while (0)
+#define InstrCountFiltered1(node, delta) \
+	do { \
+		if (((PlanState *)(node))->instrument) \
+			((PlanState *)(node))->instrument->nfiltered1 += (delta); \
+	} while(0)
+#define InstrCountFiltered2(node, delta) \
+	do { \
+		if (((PlanState *)(node))->instrument) \
+			((PlanState *)(node))->instrument->nfiltered2 += (delta); \
+	} while(0)
+
+/*
+ * EPQState is state for executing an EvalPlanQual recheck on a candidate
+ * tuples e.g. in ModifyTable or LockRows.
+ *
+ * To execute EPQ a separate EState is created (stored in ->recheckestate),
+ * which shares some resources, like the rangetable, with the main query's
+ * EState (stored in ->parentestate). The (sub-)tree of the plan that needs to
+ * be rechecked (in ->plan), is separately initialized (into
+ * ->recheckplanstate), but shares plan nodes with the corresponding nodes in
+ * the main query. The scan nodes in that separate executor tree are changed
+ * to return only the current tuple of interest for the respective
+ * table. Those tuples are either provided by the caller (using
+ * EvalPlanQualSlot), and/or found using the rowmark mechanism (non-locking
+ * rowmarks by the EPQ machinery itself, locking ones by the caller).
+ *
+ * While the plan to be checked may be changed using EvalPlanQualSetPlan() -
+ * e.g. so all source plans for a ModifyTable node can be processed - all such
+ * plans need to share the same EState.
+ */
+typedef struct EPQState
+{
+	/* Initialized at EvalPlanQualInit() time: */
+
+	EState	   *parentestate;	/* main query's EState */
+	int			epqParam;		/* ID of Param to force scan node re-eval */
+
+	/*
+	 * Tuples to be substituted by scan nodes. They need to set up, before
+	 * calling EvalPlanQual()/EvalPlanQualNext(), into the slot returned by
+	 * EvalPlanQualSlot(scanrelid). The array is indexed by scanrelid - 1.
+	 */
+	List	   *tuple_table;	/* tuple table for relsubs_slot */
+	TupleTableSlot **relsubs_slot;
+
+	/*
+	 * Initialized by EvalPlanQualInit(), may be changed later with
+	 * EvalPlanQualSetPlan():
+	 */
+
+	Plan	   *plan;			/* plan tree to be executed */
+	List	   *arowMarks;		/* ExecAuxRowMarks (non-locking only) */
+
+
+	/*
+	 * The original output tuple to be rechecked.  Set by
+	 * EvalPlanQualSetSlot(), before EvalPlanQualNext() or EvalPlanQual() may
+	 * be called.
+	 */
+	TupleTableSlot *origslot;
+
+
+	/* Initialized or reset by EvalPlanQualBegin(): */
+
+	EState	   *recheckestate;	/* EState for EPQ execution, see above */
+
+	/*
+	 * Rowmarks that can be fetched on-demand using
+	 * EvalPlanQualFetchRowMark(), indexed by scanrelid - 1. Only non-locking
+	 * rowmarks.
+	 */
+	ExecAuxRowMark **relsubs_rowmark;
+
+	/*
+	 * True if a relation's EPQ tuple has been fetched for relation, indexed
+	 * by scanrelid - 1.
+	 */
+	bool	   *relsubs_done;
+
+	PlanState  *recheckplanstate;	/* EPQ specific exec nodes, for ->plan */
+} EPQState;
+
+
+/* ----------------
+ *	 ResultState information
+ * ----------------
+ */
+typedef struct ResultState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	ExprState  *resconstantqual;
+	bool		rs_done;		/* are we done? */
+	bool		rs_checkqual;	/* do we need to check the qual? */
+} ResultState;
+
+/* ----------------
+ *	 ProjectSetState information
+ *
+ * Note: at least one of the "elems" will be a SetExprState; the rest are
+ * regular ExprStates.
+ * ----------------
+ */
+typedef struct ProjectSetState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	Node	  **elems;			/* array of expression states */
+	ExprDoneCond *elemdone;		/* array of per-SRF is-done states */
+	int			nelems;			/* length of elemdone[] array */
+	bool		pending_srf_tuples; /* still evaluating srfs in tlist? */
+	MemoryContext argcontext;	/* context for SRF arguments */
+} ProjectSetState;
+
+/* ----------------
+ *	 ModifyTableState information
+ * ----------------
+ */
+typedef struct ModifyTableState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	CmdType		operation;		/* INSERT, UPDATE, or DELETE */
+	bool		canSetTag;		/* do we set the command tag/es_processed? */
+	bool		mt_done;		/* are we done? */
+	PlanState **mt_plans;		/* subplans (one per target rel) */
+	int			mt_nplans;		/* number of plans in the array */
+	int			mt_whichplan;	/* which one is being executed (0..n-1) */
+	TupleTableSlot **mt_scans;	/* input tuple corresponding to underlying
+								 * plans */
+	ResultRelInfo *resultRelInfo;	/* per-subplan target relations */
+	ResultRelInfo *rootResultRelInfo;	/* root target relation (partitioned
+										 * table root) */
+	List	  **mt_arowmarks;	/* per-subplan ExecAuxRowMark lists */
+	EPQState	mt_epqstate;	/* for evaluating EvalPlanQual rechecks */
+	bool		fireBSTriggers; /* do we need to fire stmt triggers? */
+
+	/*
+	 * Slot for storing tuples in the root partitioned table's rowtype during
+	 * an UPDATE of a partitioned table.
+	 */
+	TupleTableSlot *mt_root_tuple_slot;
+
+	/* Tuple-routing support info */
+	struct PartitionTupleRouting *mt_partition_tuple_routing;
+
+	/* controls transition table population for specified operation */
+	struct TransitionCaptureState *mt_transition_capture;
+
+	/* controls transition table population for INSERT...ON CONFLICT UPDATE */
+	struct TransitionCaptureState *mt_oc_transition_capture;
+
+	/* Per plan map for tuple conversion from child to root */
+	TupleConversionMap **mt_per_subplan_tupconv_maps;
+} ModifyTableState;
+
+/* ----------------
+ *	 AppendState information
+ *
+ *		nplans				how many plans are in the array
+ *		whichplan			which plan is being executed (0 .. n-1), or a
+ *							special negative value. See nodeAppend.c.
+ *		prune_state			details required to allow partitions to be
+ *							eliminated from the scan, or NULL if not possible.
+ *		valid_subplans		for runtime pruning, valid appendplans indexes to
+ *							scan.
+ * ----------------
+ */
+
+struct AppendState;
+typedef struct AppendState AppendState;
+struct ParallelAppendState;
+typedef struct ParallelAppendState ParallelAppendState;
+struct PartitionPruneState;
+
+struct AppendState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	PlanState **appendplans;	/* array of PlanStates for my inputs */
+	int			as_nplans;
+	int			as_whichplan;
+	int			as_first_partial_plan;	/* Index of 'appendplans' containing
+										 * the first partial plan */
+	ParallelAppendState *as_pstate; /* parallel coordination info */
+	Size		pstate_len;		/* size of parallel coordination info */
+	struct PartitionPruneState *as_prune_state;
+	Bitmapset  *as_valid_subplans;
+	bool		(*choose_next_subplan) (AppendState *);
+};
+
+/* ----------------
+ *	 MergeAppendState information
+ *
+ *		nplans			how many plans are in the array
+ *		nkeys			number of sort key columns
+ *		sortkeys		sort keys in SortSupport representation
+ *		slots			current output tuple of each subplan
+ *		heap			heap of active tuples
+ *		initialized		true if we have fetched first tuple from each subplan
+ *		prune_state		details required to allow partitions to be
+ *						eliminated from the scan, or NULL if not possible.
+ *		valid_subplans	for runtime pruning, valid mergeplans indexes to
+ *						scan.
+ * ----------------
+ */
+typedef struct MergeAppendState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	PlanState **mergeplans;		/* array of PlanStates for my inputs */
+	int			ms_nplans;
+	int			ms_nkeys;
+	SortSupport ms_sortkeys;	/* array of length ms_nkeys */
+	TupleTableSlot **ms_slots;	/* array of length ms_nplans */
+	struct binaryheap *ms_heap; /* binary heap of slot indices */
+	bool		ms_initialized; /* are subplans started? */
+	struct PartitionPruneState *ms_prune_state;
+	Bitmapset  *ms_valid_subplans;
+} MergeAppendState;
+
+/* ----------------
+ *	 RecursiveUnionState information
+ *
+ *		RecursiveUnionState is used for performing a recursive union.
+ *
+ *		recursing			T when we're done scanning the non-recursive term
+ *		intermediate_empty	T if intermediate_table is currently empty
+ *		working_table		working table (to be scanned by recursive term)
+ *		intermediate_table	current recursive output (next generation of WT)
+ * ----------------
+ */
+typedef struct RecursiveUnionState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	bool		recursing;
+	bool		intermediate_empty;
+	Tuplestorestate *working_table;
+	Tuplestorestate *intermediate_table;
+	/* Remaining fields are unused in UNION ALL case */
+	Oid		   *eqfuncoids;		/* per-grouping-field equality fns */
+	FmgrInfo   *hashfunctions;	/* per-grouping-field hash fns */
+	MemoryContext tempContext;	/* short-term context for comparisons */
+	TupleHashTable hashtable;	/* hash table for tuples already seen */
+	MemoryContext tableContext; /* memory context containing hash table */
+} RecursiveUnionState;
+
+/* ----------------
+ *	 BitmapAndState information
+ * ----------------
+ */
+typedef struct BitmapAndState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	PlanState **bitmapplans;	/* array of PlanStates for my inputs */
+	int			nplans;			/* number of input plans */
+} BitmapAndState;
+
+/* ----------------
+ *	 BitmapOrState information
+ * ----------------
+ */
+typedef struct BitmapOrState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	PlanState **bitmapplans;	/* array of PlanStates for my inputs */
+	int			nplans;			/* number of input plans */
+} BitmapOrState;
+
+/* ----------------------------------------------------------------
+ *				 Scan State Information
+ * ----------------------------------------------------------------
+ */
+
+/* ----------------
+ *	 ScanState information
+ *
+ *		ScanState extends PlanState for node types that represent
+ *		scans of an underlying relation.  It can also be used for nodes
+ *		that scan the output of an underlying plan node --- in that case,
+ *		only ScanTupleSlot is actually useful, and it refers to the tuple
+ *		retrieved from the subplan.
+ *
+ *		currentRelation    relation being scanned (NULL if none)
+ *		currentScanDesc    current scan descriptor for scan (NULL if none)
+ *		ScanTupleSlot	   pointer to slot in tuple table holding scan tuple
+ * ----------------
+ */
+typedef struct ScanState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	Relation	ss_currentRelation;
+	struct TableScanDescData *ss_currentScanDesc;
+	TupleTableSlot *ss_ScanTupleSlot;
+} ScanState;
+
+/* ----------------
+ *	 SeqScanState information
+ * ----------------
+ */
+typedef struct SeqScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	Size		pscan_len;		/* size of parallel heap scan descriptor */
+} SeqScanState;
+
+/* ----------------
+ *	 SampleScanState information
+ * ----------------
+ */
+typedef struct SampleScanState
+{
+	ScanState	ss;
+	List	   *args;			/* expr states for TABLESAMPLE params */
+	ExprState  *repeatable;		/* expr state for REPEATABLE expr */
+	/* use struct pointer to avoid including tsmapi.h here */
+	struct TsmRoutine *tsmroutine;	/* descriptor for tablesample method */
+	void	   *tsm_state;		/* tablesample method can keep state here */
+	bool		use_bulkread;	/* use bulkread buffer access strategy? */
+	bool		use_pagemode;	/* use page-at-a-time visibility checking? */
+	bool		begun;			/* false means need to call BeginSampleScan */
+	uint32		seed;			/* random seed */
+	int64		donetuples;		/* number of tuples already returned */
+	bool		haveblock;		/* has a block for sampling been determined */
+	bool		done;			/* exhausted all tuples? */
+} SampleScanState;
+
+/*
+ * These structs store information about index quals that don't have simple
+ * constant right-hand sides.  See comments for ExecIndexBuildScanKeys()
+ * for discussion.
+ */
+typedef struct
+{
+	struct ScanKeyData *scan_key;	/* scankey to put value into */
+	ExprState  *key_expr;		/* expr to evaluate to get value */
+	bool		key_toastable;	/* is expr's result a toastable datatype? */
+} IndexRuntimeKeyInfo;
+
+typedef struct
+{
+	struct ScanKeyData *scan_key;	/* scankey to put value into */
+	ExprState  *array_expr;		/* expr to evaluate to get array value */
+	int			next_elem;		/* next array element to use */
+	int			num_elems;		/* number of elems in current array value */
+	Datum	   *elem_values;	/* array of num_elems Datums */
+	bool	   *elem_nulls;		/* array of num_elems is-null flags */
+} IndexArrayKeyInfo;
+
+/* ----------------
+ *	 IndexScanState information
+ *
+ *		indexqualorig	   execution state for indexqualorig expressions
+ *		indexorderbyorig   execution state for indexorderbyorig expressions
+ *		ScanKeys		   Skey structures for index quals
+ *		NumScanKeys		   number of ScanKeys
+ *		OrderByKeys		   Skey structures for index ordering operators
+ *		NumOrderByKeys	   number of OrderByKeys
+ *		RuntimeKeys		   info about Skeys that must be evaluated at runtime
+ *		NumRuntimeKeys	   number of RuntimeKeys
+ *		RuntimeKeysReady   true if runtime Skeys have been computed
+ *		RuntimeContext	   expr context for evaling runtime Skeys
+ *		RelationDesc	   index relation descriptor
+ *		ScanDesc		   index scan descriptor
+ *
+ *		ReorderQueue	   tuples that need reordering due to re-check
+ *		ReachedEnd		   have we fetched all tuples from index already?
+ *		OrderByValues	   values of ORDER BY exprs of last fetched tuple
+ *		OrderByNulls	   null flags for OrderByValues
+ *		SortSupport		   for reordering ORDER BY exprs
+ *		OrderByTypByVals   is the datatype of order by expression pass-by-value?
+ *		OrderByTypLens	   typlens of the datatypes of order by expressions
+ *		PscanLen		   size of parallel index scan descriptor
+ * ----------------
+ */
+typedef struct IndexScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	ExprState  *indexqualorig;
+	List	   *indexorderbyorig;
+	struct ScanKeyData *iss_ScanKeys;
+	int			iss_NumScanKeys;
+	struct ScanKeyData *iss_OrderByKeys;
+	int			iss_NumOrderByKeys;
+	IndexRuntimeKeyInfo *iss_RuntimeKeys;
+	int			iss_NumRuntimeKeys;
+	bool		iss_RuntimeKeysReady;
+	ExprContext *iss_RuntimeContext;
+	Relation	iss_RelationDesc;
+	struct IndexScanDescData *iss_ScanDesc;
+
+	/* These are needed for re-checking ORDER BY expr ordering */
+	pairingheap *iss_ReorderQueue;
+	bool		iss_ReachedEnd;
+	Datum	   *iss_OrderByValues;
+	bool	   *iss_OrderByNulls;
+	SortSupport iss_SortSupport;
+	bool	   *iss_OrderByTypByVals;
+	int16	   *iss_OrderByTypLens;
+	Size		iss_PscanLen;
+} IndexScanState;
+
+/* ----------------
+ *	 IndexOnlyScanState information
+ *
+ *		indexqual		   execution state for indexqual expressions
+ *		ScanKeys		   Skey structures for index quals
+ *		NumScanKeys		   number of ScanKeys
+ *		OrderByKeys		   Skey structures for index ordering operators
+ *		NumOrderByKeys	   number of OrderByKeys
+ *		RuntimeKeys		   info about Skeys that must be evaluated at runtime
+ *		NumRuntimeKeys	   number of RuntimeKeys
+ *		RuntimeKeysReady   true if runtime Skeys have been computed
+ *		RuntimeContext	   expr context for evaling runtime Skeys
+ *		RelationDesc	   index relation descriptor
+ *		ScanDesc		   index scan descriptor
+ *		TableSlot		   slot for holding tuples fetched from the table
+ *		VMBuffer		   buffer in use for visibility map testing, if any
+ *		PscanLen		   size of parallel index-only scan descriptor
+ * ----------------
+ */
+typedef struct IndexOnlyScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	ExprState  *indexqual;
+	struct ScanKeyData *ioss_ScanKeys;
+	int			ioss_NumScanKeys;
+	struct ScanKeyData *ioss_OrderByKeys;
+	int			ioss_NumOrderByKeys;
+	IndexRuntimeKeyInfo *ioss_RuntimeKeys;
+	int			ioss_NumRuntimeKeys;
+	bool		ioss_RuntimeKeysReady;
+	ExprContext *ioss_RuntimeContext;
+	Relation	ioss_RelationDesc;
+	struct IndexScanDescData *ioss_ScanDesc;
+	TupleTableSlot *ioss_TableSlot;
+	Buffer		ioss_VMBuffer;
+	Size		ioss_PscanLen;
+} IndexOnlyScanState;
+
+/* ----------------
+ *	 BitmapIndexScanState information
+ *
+ *		result			   bitmap to return output into, or NULL
+ *		ScanKeys		   Skey structures for index quals
+ *		NumScanKeys		   number of ScanKeys
+ *		RuntimeKeys		   info about Skeys that must be evaluated at runtime
+ *		NumRuntimeKeys	   number of RuntimeKeys
+ *		ArrayKeys		   info about Skeys that come from ScalarArrayOpExprs
+ *		NumArrayKeys	   number of ArrayKeys
+ *		RuntimeKeysReady   true if runtime Skeys have been computed
+ *		RuntimeContext	   expr context for evaling runtime Skeys
+ *		RelationDesc	   index relation descriptor
+ *		ScanDesc		   index scan descriptor
+ * ----------------
+ */
+typedef struct BitmapIndexScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	TIDBitmap  *biss_result;
+	struct ScanKeyData *biss_ScanKeys;
+	int			biss_NumScanKeys;
+	IndexRuntimeKeyInfo *biss_RuntimeKeys;
+	int			biss_NumRuntimeKeys;
+	IndexArrayKeyInfo *biss_ArrayKeys;
+	int			biss_NumArrayKeys;
+	bool		biss_RuntimeKeysReady;
+	ExprContext *biss_RuntimeContext;
+	Relation	biss_RelationDesc;
+	struct IndexScanDescData *biss_ScanDesc;
+} BitmapIndexScanState;
+
+/* ----------------
+ *	 SharedBitmapState information
+ *
+ *		BM_INITIAL		TIDBitmap creation is not yet started, so first worker
+ *						to see this state will set the state to BM_INPROGRESS
+ *						and that process will be responsible for creating
+ *						TIDBitmap.
+ *		BM_INPROGRESS	TIDBitmap creation is in progress; workers need to
+ *						sleep until it's finished.
+ *		BM_FINISHED		TIDBitmap creation is done, so now all workers can
+ *						proceed to iterate over TIDBitmap.
+ * ----------------
+ */
+typedef enum
+{
+	BM_INITIAL,
+	BM_INPROGRESS,
+	BM_FINISHED
+} SharedBitmapState;
+
+/* ----------------
+ *	 ParallelBitmapHeapState information
+ *		tbmiterator				iterator for scanning current pages
+ *		prefetch_iterator		iterator for prefetching ahead of current page
+ *		mutex					mutual exclusion for the prefetching variable
+ *								and state
+ *		prefetch_pages			# pages prefetch iterator is ahead of current
+ *		prefetch_target			current target prefetch distance
+ *		state					current state of the TIDBitmap
+ *		cv						conditional wait variable
+ *		phs_snapshot_data		snapshot data shared to workers
+ * ----------------
+ */
+typedef struct ParallelBitmapHeapState
+{
+	dsa_pointer tbmiterator;
+	dsa_pointer prefetch_iterator;
+	slock_t		mutex;
+	int			prefetch_pages;
+	int			prefetch_target;
+	SharedBitmapState state;
+	ConditionVariable cv;
+	char		phs_snapshot_data[FLEXIBLE_ARRAY_MEMBER];
+} ParallelBitmapHeapState;
+
+/* ----------------
+ *	 BitmapHeapScanState information
+ *
+ *		bitmapqualorig	   execution state for bitmapqualorig expressions
+ *		tbm				   bitmap obtained from child index scan(s)
+ *		tbmiterator		   iterator for scanning current pages
+ *		tbmres			   current-page data
+ *		can_skip_fetch	   can we potentially skip tuple fetches in this scan?
+ *		return_empty_tuples number of empty tuples to return
+ *		vmbuffer		   buffer for visibility-map lookups
+ *		pvmbuffer		   ditto, for prefetched pages
+ *		exact_pages		   total number of exact pages retrieved
+ *		lossy_pages		   total number of lossy pages retrieved
+ *		prefetch_iterator  iterator for prefetching ahead of current page
+ *		prefetch_pages	   # pages prefetch iterator is ahead of current
+ *		prefetch_target    current target prefetch distance
+ *		prefetch_maximum   maximum value for prefetch_target
+ *		pscan_len		   size of the shared memory for parallel bitmap
+ *		initialized		   is node is ready to iterate
+ *		shared_tbmiterator	   shared iterator
+ *		shared_prefetch_iterator shared iterator for prefetching
+ *		pstate			   shared state for parallel bitmap scan
+ * ----------------
+ */
+typedef struct BitmapHeapScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	ExprState  *bitmapqualorig;
+	TIDBitmap  *tbm;
+	TBMIterator *tbmiterator;
+	TBMIterateResult *tbmres;
+	bool		can_skip_fetch;
+	int			return_empty_tuples;
+	Buffer		vmbuffer;
+	Buffer		pvmbuffer;
+	long		exact_pages;
+	long		lossy_pages;
+	TBMIterator *prefetch_iterator;
+	int			prefetch_pages;
+	int			prefetch_target;
+	int			prefetch_maximum;
+	Size		pscan_len;
+	bool		initialized;
+	TBMSharedIterator *shared_tbmiterator;
+	TBMSharedIterator *shared_prefetch_iterator;
+	ParallelBitmapHeapState *pstate;
+} BitmapHeapScanState;
+
+/* ----------------
+ *	 TidScanState information
+ *
+ *		tidexprs	   list of TidExpr structs (see nodeTidscan.c)
+ *		isCurrentOf    scan has a CurrentOfExpr qual
+ *		NumTids		   number of tids in this scan
+ *		TidPtr		   index of currently fetched tid
+ *		TidList		   evaluated item pointers (array of size NumTids)
+ *		htup		   currently-fetched tuple, if any
+ * ----------------
+ */
+typedef struct TidScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	List	   *tss_tidexprs;
+	bool		tss_isCurrentOf;
+	int			tss_NumTids;
+	int			tss_TidPtr;
+	ItemPointerData *tss_TidList;
+	HeapTupleData tss_htup;
+} TidScanState;
+
+/* ----------------
+ *	 SubqueryScanState information
+ *
+ *		SubqueryScanState is used for scanning a sub-query in the range table.
+ *		ScanTupleSlot references the current output tuple of the sub-query.
+ * ----------------
+ */
+typedef struct SubqueryScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	PlanState  *subplan;
+} SubqueryScanState;
+
+/* ----------------
+ *	 FunctionScanState information
+ *
+ *		Function nodes are used to scan the results of a
+ *		function appearing in FROM (typically a function returning set).
+ *
+ *		eflags				node's capability flags
+ *		ordinality			is this scan WITH ORDINALITY?
+ *		simple				true if we have 1 function and no ordinality
+ *		ordinal				current ordinal column value
+ *		nfuncs				number of functions being executed
+ *		funcstates			per-function execution states (private in
+ *							nodeFunctionscan.c)
+ *		argcontext			memory context to evaluate function arguments in
+ * ----------------
+ */
+struct FunctionScanPerFuncState;
+
+typedef struct FunctionScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	int			eflags;
+	bool		ordinality;
+	bool		simple;
+	int64		ordinal;
+	int			nfuncs;
+	struct FunctionScanPerFuncState *funcstates;	/* array of length nfuncs */
+	MemoryContext argcontext;
+} FunctionScanState;
+
+/* ----------------
+ *	 ValuesScanState information
+ *
+ *		ValuesScan nodes are used to scan the results of a VALUES list
+ *
+ *		rowcontext			per-expression-list context
+ *		exprlists			array of expression lists being evaluated
+ *		exprstatelists		array of expression state lists, for SubPlans only
+ *		array_len			size of above arrays
+ *		curr_idx			current array index (0-based)
+ *
+ *	Note: ss.ps.ps_ExprContext is used to evaluate any qual or projection
+ *	expressions attached to the node.  We create a second ExprContext,
+ *	rowcontext, in which to build the executor expression state for each
+ *	Values sublist.  Resetting this context lets us get rid of expression
+ *	state for each row, avoiding major memory leakage over a long values list.
+ *	However, that doesn't work for sublists containing SubPlans, because a
+ *	SubPlan has to be connected up to the outer plan tree to work properly.
+ *	Therefore, for only those sublists containing SubPlans, we do expression
+ *	state construction at executor start, and store those pointers in
+ *	exprstatelists[].  NULL entries in that array correspond to simple
+ *	subexpressions that are handled as described above.
+ * ----------------
+ */
+typedef struct ValuesScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	ExprContext *rowcontext;
+	List	  **exprlists;
+	List	  **exprstatelists;
+	int			array_len;
+	int			curr_idx;
+} ValuesScanState;
+
+/* ----------------
+ *		TableFuncScanState node
+ *
+ * Used in table-expression functions like XMLTABLE.
+ * ----------------
+ */
+typedef struct TableFuncScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	ExprState  *docexpr;		/* state for document expression */
+	ExprState  *rowexpr;		/* state for row-generating expression */
+	List	   *colexprs;		/* state for column-generating expression */
+	List	   *coldefexprs;	/* state for column default expressions */
+	List	   *ns_names;		/* same as TableFunc.ns_names */
+	List	   *ns_uris;		/* list of states of namespace URI exprs */
+	Bitmapset  *notnulls;		/* nullability flag for each output column */
+	void	   *opaque;			/* table builder private space */
+	const struct TableFuncRoutine *routine; /* table builder methods */
+	FmgrInfo   *in_functions;	/* input function for each column */
+	Oid		   *typioparams;	/* typioparam for each column */
+	int64		ordinal;		/* row number to be output next */
+	MemoryContext perTableCxt;	/* per-table context */
+	Tuplestorestate *tupstore;	/* output tuple store */
+} TableFuncScanState;
+
+/* ----------------
+ *	 CteScanState information
+ *
+ *		CteScan nodes are used to scan a CommonTableExpr query.
+ *
+ * Multiple CteScan nodes can read out from the same CTE query.  We use
+ * a tuplestore to hold rows that have been read from the CTE query but
+ * not yet consumed by all readers.
+ * ----------------
+ */
+typedef struct CteScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	int			eflags;			/* capability flags to pass to tuplestore */
+	int			readptr;		/* index of my tuplestore read pointer */
+	PlanState  *cteplanstate;	/* PlanState for the CTE query itself */
+	/* Link to the "leader" CteScanState (possibly this same node) */
+	struct CteScanState *leader;
+	/* The remaining fields are only valid in the "leader" CteScanState */
+	Tuplestorestate *cte_table; /* rows already read from the CTE query */
+	bool		eof_cte;		/* reached end of CTE query? */
+} CteScanState;
+
+/* ----------------
+ *	 NamedTuplestoreScanState information
+ *
+ *		NamedTuplestoreScan nodes are used to scan a Tuplestore created and
+ *		named prior to execution of the query.  An example is a transition
+ *		table for an AFTER trigger.
+ *
+ * Multiple NamedTuplestoreScan nodes can read out from the same Tuplestore.
+ * ----------------
+ */
+typedef struct NamedTuplestoreScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	int			readptr;		/* index of my tuplestore read pointer */
+	TupleDesc	tupdesc;		/* format of the tuples in the tuplestore */
+	Tuplestorestate *relation;	/* the rows */
+} NamedTuplestoreScanState;
+
+/* ----------------
+ *	 WorkTableScanState information
+ *
+ *		WorkTableScan nodes are used to scan the work table created by
+ *		a RecursiveUnion node.  We locate the RecursiveUnion node
+ *		during executor startup.
+ * ----------------
+ */
+typedef struct WorkTableScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	RecursiveUnionState *rustate;
+} WorkTableScanState;
+
+/* ----------------
+ *	 ForeignScanState information
+ *
+ *		ForeignScan nodes are used to scan foreign-data tables.
+ * ----------------
+ */
+typedef struct ForeignScanState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	ExprState  *fdw_recheck_quals;	/* original quals not in ss.ps.qual */
+	Size		pscan_len;		/* size of parallel coordination information */
+	/* use struct pointer to avoid including fdwapi.h here */
+	struct FdwRoutine *fdwroutine;
+	void	   *fdw_state;		/* foreign-data wrapper can keep state here */
+} ForeignScanState;
+
+/* ----------------
+ *	 CustomScanState information
+ *
+ *		CustomScan nodes are used to execute custom code within executor.
+ *
+ * Core code must avoid assuming that the CustomScanState is only as large as
+ * the structure declared here; providers are allowed to make it the first
+ * element in a larger structure, and typically would need to do so.  The
+ * struct is actually allocated by the CreateCustomScanState method associated
+ * with the plan node.  Any additional fields can be initialized there, or in
+ * the BeginCustomScan method.
+ * ----------------
+ */
+struct CustomExecMethods;
+
+typedef struct CustomScanState
+{
+	ScanState	ss;
+	uint32		flags;			/* mask of CUSTOMPATH_* flags, see
+								 * nodes/extensible.h */
+	List	   *custom_ps;		/* list of child PlanState nodes, if any */
+	Size		pscan_len;		/* size of parallel coordination information */
+	const struct CustomExecMethods *methods;
+} CustomScanState;
+
+/* ----------------------------------------------------------------
+ *				 Join State Information
+ * ----------------------------------------------------------------
+ */
+
+/* ----------------
+ *	 JoinState information
+ *
+ *		Superclass for state nodes of join plans.
+ * ----------------
+ */
+typedef struct JoinState
+{
+	PlanState	ps;
+	JoinType	jointype;
+	bool		single_match;	/* True if we should skip to next outer tuple
+								 * after finding one inner match */
+	ExprState  *joinqual;		/* JOIN quals (in addition to ps.qual) */
+} JoinState;
+
+/* ----------------
+ *	 NestLoopState information
+ *
+ *		NeedNewOuter	   true if need new outer tuple on next call
+ *		MatchedOuter	   true if found a join match for current outer tuple
+ *		NullInnerTupleSlot prepared null tuple for left outer joins
+ * ----------------
+ */
+typedef struct NestLoopState
+{
+	JoinState	js;				/* its first field is NodeTag */
+	bool		nl_NeedNewOuter;
+	bool		nl_MatchedOuter;
+	TupleTableSlot *nl_NullInnerTupleSlot;
+} NestLoopState;
+
+/* ----------------
+ *	 MergeJoinState information
+ *
+ *		NumClauses		   number of mergejoinable join clauses
+ *		Clauses			   info for each mergejoinable clause
+ *		JoinState		   current state of ExecMergeJoin state machine
+ *		SkipMarkRestore    true if we may skip Mark and Restore operations
+ *		ExtraMarks		   true to issue extra Mark operations on inner scan
+ *		ConstFalseJoin	   true if we have a constant-false joinqual
+ *		FillOuter		   true if should emit unjoined outer tuples anyway
+ *		FillInner		   true if should emit unjoined inner tuples anyway
+ *		MatchedOuter	   true if found a join match for current outer tuple
+ *		MatchedInner	   true if found a join match for current inner tuple
+ *		OuterTupleSlot	   slot in tuple table for cur outer tuple
+ *		InnerTupleSlot	   slot in tuple table for cur inner tuple
+ *		MarkedTupleSlot    slot in tuple table for marked tuple
+ *		NullOuterTupleSlot prepared null tuple for right outer joins
+ *		NullInnerTupleSlot prepared null tuple for left outer joins
+ *		OuterEContext	   workspace for computing outer tuple's join values
+ *		InnerEContext	   workspace for computing inner tuple's join values
+ * ----------------
+ */
+/* private in nodeMergejoin.c: */
+typedef struct MergeJoinClauseData *MergeJoinClause;
+
+typedef struct MergeJoinState
+{
+	JoinState	js;				/* its first field is NodeTag */
+	int			mj_NumClauses;
+	MergeJoinClause mj_Clauses; /* array of length mj_NumClauses */
+	int			mj_JoinState;
+	bool		mj_SkipMarkRestore;
+	bool		mj_ExtraMarks;
+	bool		mj_ConstFalseJoin;
+	bool		mj_FillOuter;
+	bool		mj_FillInner;
+	bool		mj_MatchedOuter;
+	bool		mj_MatchedInner;
+	TupleTableSlot *mj_OuterTupleSlot;
+	TupleTableSlot *mj_InnerTupleSlot;
+	TupleTableSlot *mj_MarkedTupleSlot;
+	TupleTableSlot *mj_NullOuterTupleSlot;
+	TupleTableSlot *mj_NullInnerTupleSlot;
+	ExprContext *mj_OuterEContext;
+	ExprContext *mj_InnerEContext;
+} MergeJoinState;
+
+/* ----------------
+ *	 HashJoinState information
+ *
+ *		hashclauses				original form of the hashjoin condition
+ *		hj_OuterHashKeys		the outer hash keys in the hashjoin condition
+ *		hj_HashOperators		the join operators in the hashjoin condition
+ *		hj_HashTable			hash table for the hashjoin
+ *								(NULL if table not built yet)
+ *		hj_CurHashValue			hash value for current outer tuple
+ *		hj_CurBucketNo			regular bucket# for current outer tuple
+ *		hj_CurSkewBucketNo		skew bucket# for current outer tuple
+ *		hj_CurTuple				last inner tuple matched to current outer
+ *								tuple, or NULL if starting search
+ *								(hj_CurXXX variables are undefined if
+ *								OuterTupleSlot is empty!)
+ *		hj_OuterTupleSlot		tuple slot for outer tuples
+ *		hj_HashTupleSlot		tuple slot for inner (hashed) tuples
+ *		hj_NullOuterTupleSlot	prepared null tuple for right/full outer joins
+ *		hj_NullInnerTupleSlot	prepared null tuple for left/full outer joins
+ *		hj_FirstOuterTupleSlot	first tuple retrieved from outer plan
+ *		hj_JoinState			current state of ExecHashJoin state machine
+ *		hj_MatchedOuter			true if found a join match for current outer
+ *		hj_OuterNotEmpty		true if outer relation known not empty
+ * ----------------
+ */
+
+/* these structs are defined in executor/hashjoin.h: */
+typedef struct HashJoinTupleData *HashJoinTuple;
+typedef struct HashJoinTableData *HashJoinTable;
+
+typedef struct HashJoinState
+{
+	JoinState	js;				/* its first field is NodeTag */
+	ExprState  *hashclauses;
+	List	   *hj_OuterHashKeys;	/* list of ExprState nodes */
+	List	   *hj_HashOperators;	/* list of operator OIDs */
+	List	   *hj_Collations;
+	HashJoinTable hj_HashTable;
+	uint32		hj_CurHashValue;
+	int			hj_CurBucketNo;
+	int			hj_CurSkewBucketNo;
+	HashJoinTuple hj_CurTuple;
+	TupleTableSlot *hj_OuterTupleSlot;
+	TupleTableSlot *hj_HashTupleSlot;
+	TupleTableSlot *hj_NullOuterTupleSlot;
+	TupleTableSlot *hj_NullInnerTupleSlot;
+	TupleTableSlot *hj_FirstOuterTupleSlot;
+	int			hj_JoinState;
+	bool		hj_MatchedOuter;
+	bool		hj_OuterNotEmpty;
+} HashJoinState;
+
+
+/* ----------------------------------------------------------------
+ *				 Materialization State Information
+ * ----------------------------------------------------------------
+ */
+
+/* ----------------
+ *	 MaterialState information
+ *
+ *		materialize nodes are used to materialize the results
+ *		of a subplan into a temporary file.
+ *
+ *		ss.ss_ScanTupleSlot refers to output of underlying plan.
+ * ----------------
+ */
+typedef struct MaterialState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	int			eflags;			/* capability flags to pass to tuplestore */
+	bool		eof_underlying; /* reached end of underlying plan? */
+	Tuplestorestate *tuplestorestate;
+} MaterialState;
+
+
+/* ----------------
+ *	 When performing sorting by multiple keys, it's possible that the input
+ *	 dataset is already sorted on a prefix of those keys. We call these
+ *	 "presorted keys".
+ *	 PresortedKeyData represents information about one such key.
+ * ----------------
+ */
+typedef struct PresortedKeyData
+{
+	FmgrInfo	flinfo;			/* comparison function info */
+	FunctionCallInfo fcinfo;	/* comparison function call info */
+	OffsetNumber attno;			/* attribute number in tuple */
+} PresortedKeyData;
+
+/* ----------------
+ *	 Shared memory container for per-worker sort information
+ * ----------------
+ */
+typedef struct SharedSortInfo
+{
+	int			num_workers;
+	TuplesortInstrumentation sinstrument[FLEXIBLE_ARRAY_MEMBER];
+} SharedSortInfo;
+
+/* ----------------
+ *	 SortState information
+ * ----------------
+ */
+typedef struct SortState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	bool		randomAccess;	/* need random access to sort output? */
+	bool		bounded;		/* is the result set bounded? */
+	int64		bound;			/* if bounded, how many tuples are needed */
+	bool		sort_Done;		/* sort completed yet? */
+	bool		bounded_Done;	/* value of bounded we did the sort with */
+	int64		bound_Done;		/* value of bound we did the sort with */
+	void	   *tuplesortstate; /* private state of tuplesort.c */
+	bool		am_worker;		/* are we a worker? */
+	SharedSortInfo *shared_info;	/* one entry per worker */
+} SortState;
+
+/* ----------------
+ *	 Instrumentation information for IncrementalSort
+ * ----------------
+ */
+typedef struct IncrementalSortGroupInfo
+{
+	int64		groupCount;
+	int64		maxDiskSpaceUsed;
+	int64		totalDiskSpaceUsed;
+	int64		maxMemorySpaceUsed;
+	int64		totalMemorySpaceUsed;
+	bits32		sortMethods;	/* bitmask of TuplesortMethod */
+} IncrementalSortGroupInfo;
+
+typedef struct IncrementalSortInfo
+{
+	IncrementalSortGroupInfo fullsortGroupInfo;
+	IncrementalSortGroupInfo prefixsortGroupInfo;
+} IncrementalSortInfo;
+
+/* ----------------
+ *	 Shared memory container for per-worker incremental sort information
+ * ----------------
+ */
+typedef struct SharedIncrementalSortInfo
+{
+	int			num_workers;
+	IncrementalSortInfo sinfo[FLEXIBLE_ARRAY_MEMBER];
+} SharedIncrementalSortInfo;
+
+/* ----------------
+ *	 IncrementalSortState information
+ * ----------------
+ */
+typedef enum
+{
+	INCSORT_LOADFULLSORT,
+	INCSORT_LOADPREFIXSORT,
+	INCSORT_READFULLSORT,
+	INCSORT_READPREFIXSORT,
+} IncrementalSortExecutionStatus;
+
+typedef struct IncrementalSortState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	bool		bounded;		/* is the result set bounded? */
+	int64		bound;			/* if bounded, how many tuples are needed */
+	bool		outerNodeDone;	/* finished fetching tuples from outer node */
+	int64		bound_Done;		/* value of bound we did the sort with */
+	IncrementalSortExecutionStatus execution_status;
+	int64		n_fullsort_remaining;
+	Tuplesortstate *fullsort_state; /* private state of tuplesort.c */
+	Tuplesortstate *prefixsort_state;	/* private state of tuplesort.c */
+	/* the keys by which the input path is already sorted */
+	PresortedKeyData *presorted_keys;
+
+	IncrementalSortInfo incsort_info;
+
+	/* slot for pivot tuple defining values of presorted keys within group */
+	TupleTableSlot *group_pivot;
+	TupleTableSlot *transfer_tuple;
+	bool		am_worker;		/* are we a worker? */
+	SharedIncrementalSortInfo *shared_info; /* one entry per worker */
+} IncrementalSortState;
+
+/* ---------------------
+ *	GroupState information
+ * ---------------------
+ */
+typedef struct GroupState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	ExprState  *eqfunction;		/* equality function */
+	bool		grp_done;		/* indicates completion of Group scan */
+} GroupState;
+
+/* ---------------------
+ *	per-worker aggregate information
+ * ---------------------
+ */
+typedef struct AggregateInstrumentation
+{
+	Size		hash_mem_peak;	/* peak hash table memory usage */
+	uint64		hash_disk_used; /* kB of disk space used */
+	int			hash_batches_used;	/* batches used during entire execution */
+} AggregateInstrumentation;
+
+/* ----------------
+ *	 Shared memory container for per-worker aggregate information
+ * ----------------
+ */
+typedef struct SharedAggInfo
+{
+	int			num_workers;
+	AggregateInstrumentation sinstrument[FLEXIBLE_ARRAY_MEMBER];
+} SharedAggInfo;
+
+/* ---------------------
+ *	AggState information
+ *
+ *	ss.ss_ScanTupleSlot refers to output of underlying plan.
+ *
+ *	Note: ss.ps.ps_ExprContext contains ecxt_aggvalues and
+ *	ecxt_aggnulls arrays, which hold the computed agg values for the current
+ *	input group during evaluation of an Agg node's output tuple(s).  We
+ *	create a second ExprContext, tmpcontext, in which to evaluate input
+ *	expressions and run the aggregate transition functions.
+ * ---------------------
+ */
+/* these structs are private in nodeAgg.c: */
+typedef struct AggStatePerAggData *AggStatePerAgg;
+typedef struct AggStatePerTransData *AggStatePerTrans;
+typedef struct AggStatePerGroupData *AggStatePerGroup;
+typedef struct AggStatePerPhaseData *AggStatePerPhase;
+typedef struct AggStatePerHashData *AggStatePerHash;
+
+typedef struct AggState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+	List	   *aggs;			/* all Aggref nodes in targetlist & quals */
+	int			numaggs;		/* length of list (could be zero!) */
+	int			numtrans;		/* number of pertrans items */
+	AggStrategy aggstrategy;	/* strategy mode */
+	AggSplit	aggsplit;		/* agg-splitting mode, see nodes.h */
+	AggStatePerPhase phase;		/* pointer to current phase data */
+	int			numphases;		/* number of phases (including phase 0) */
+	int			current_phase;	/* current phase number */
+	AggStatePerAgg peragg;		/* per-Aggref information */
+	AggStatePerTrans pertrans;	/* per-Trans state information */
+	ExprContext *hashcontext;	/* econtexts for long-lived data (hashtable) */
+	ExprContext **aggcontexts;	/* econtexts for long-lived data (per GS) */
+	ExprContext *tmpcontext;	/* econtext for input expressions */
+#define FIELDNO_AGGSTATE_CURAGGCONTEXT 14
+	ExprContext *curaggcontext; /* currently active aggcontext */
+	AggStatePerAgg curperagg;	/* currently active aggregate, if any */
+#define FIELDNO_AGGSTATE_CURPERTRANS 16
+	AggStatePerTrans curpertrans;	/* currently active trans state, if any */
+	bool		input_done;		/* indicates end of input */
+	bool		agg_done;		/* indicates completion of Agg scan */
+	int			projected_set;	/* The last projected grouping set */
+#define FIELDNO_AGGSTATE_CURRENT_SET 20
+	int			current_set;	/* The current grouping set being evaluated */
+	Bitmapset  *grouped_cols;	/* grouped cols in current projection */
+	List	   *all_grouped_cols;	/* list of all grouped cols in DESC order */
+	Bitmapset  *colnos_needed;	/* all columns needed from the outer plan */
+	int			max_colno_needed;	/* highest colno needed from outer plan */
+	bool		all_cols_needed;	/* are all cols from outer plan needed? */
+	/* These fields are for grouping set phase data */
+	int			maxsets;		/* The max number of sets in any phase */
+	AggStatePerPhase phases;	/* array of all phases */
+	Tuplesortstate *sort_in;	/* sorted input to phases > 1 */
+	Tuplesortstate *sort_out;	/* input is copied here for next phase */
+	TupleTableSlot *sort_slot;	/* slot for sort results */
+	/* these fields are used in AGG_PLAIN and AGG_SORTED modes: */
+	AggStatePerGroup *pergroups;	/* grouping set indexed array of per-group
+									 * pointers */
+	HeapTuple	grp_firstTuple; /* copy of first tuple of current group */
+	/* these fields are used in AGG_HASHED and AGG_MIXED modes: */
+	bool		table_filled;	/* hash table filled yet? */
+	int			num_hashes;
+	MemoryContext hash_metacxt; /* memory for hash table itself */
+	struct HashTapeInfo *hash_tapeinfo; /* metadata for spill tapes */
+	struct HashAggSpill *hash_spills;	/* HashAggSpill for each grouping set,
+										 * exists only during first pass */
+	TupleTableSlot *hash_spill_rslot;	/* for reading spill files */
+	TupleTableSlot *hash_spill_wslot;	/* for writing spill files */
+	List	   *hash_batches;	/* hash batches remaining to be processed */
+	bool		hash_ever_spilled;	/* ever spilled during this execution? */
+	bool		hash_spill_mode;	/* we hit a limit during the current batch
+									 * and we must not create new groups */
+	Size		hash_mem_limit; /* limit before spilling hash table */
+	uint64		hash_ngroups_limit; /* limit before spilling hash table */
+	int			hash_planned_partitions;	/* number of partitions planned
+											 * for first pass */
+	double		hashentrysize;	/* estimate revised during execution */
+	Size		hash_mem_peak;	/* peak hash table memory usage */
+	uint64		hash_ngroups_current;	/* number of groups currently in
+										 * memory in all hash tables */
+	uint64		hash_disk_used; /* kB of disk space used */
+	int			hash_batches_used;	/* batches used during entire execution */
+
+	AggStatePerHash perhash;	/* array of per-hashtable data */
+	AggStatePerGroup *hash_pergroup;	/* grouping set indexed array of
+										 * per-group pointers */
+
+	/* support for evaluation of agg input expressions: */
+#define FIELDNO_AGGSTATE_ALL_PERGROUPS 53
+	AggStatePerGroup *all_pergroups;	/* array of first ->pergroups, than
+										 * ->hash_pergroup */
+	ProjectionInfo *combinedproj;	/* projection machinery */
+	SharedAggInfo *shared_info; /* one entry per worker */
+} AggState;
+
+/* ----------------
+ *	WindowAggState information
+ * ----------------
+ */
+/* these structs are private in nodeWindowAgg.c: */
+typedef struct WindowStatePerFuncData *WindowStatePerFunc;
+typedef struct WindowStatePerAggData *WindowStatePerAgg;
+
+typedef struct WindowAggState
+{
+	ScanState	ss;				/* its first field is NodeTag */
+
+	/* these fields are filled in by ExecInitExpr: */
+	List	   *funcs;			/* all WindowFunc nodes in targetlist */
+	int			numfuncs;		/* total number of window functions */
+	int			numaggs;		/* number that are plain aggregates */
+
+	WindowStatePerFunc perfunc; /* per-window-function information */
+	WindowStatePerAgg peragg;	/* per-plain-aggregate information */
+	ExprState  *partEqfunction; /* equality funcs for partition columns */
+	ExprState  *ordEqfunction;	/* equality funcs for ordering columns */
+	Tuplestorestate *buffer;	/* stores rows of current partition */
+	int			current_ptr;	/* read pointer # for current row */
+	int			framehead_ptr;	/* read pointer # for frame head, if used */
+	int			frametail_ptr;	/* read pointer # for frame tail, if used */
+	int			grouptail_ptr;	/* read pointer # for group tail, if used */
+	int64		spooled_rows;	/* total # of rows in buffer */
+	int64		currentpos;		/* position of current row in partition */
+	int64		frameheadpos;	/* current frame head position */
+	int64		frametailpos;	/* current frame tail position (frame end+1) */
+	/* use struct pointer to avoid including windowapi.h here */
+	struct WindowObjectData *agg_winobj;	/* winobj for aggregate fetches */
+	int64		aggregatedbase; /* start row for current aggregates */
+	int64		aggregatedupto; /* rows before this one are aggregated */
+
+	int			frameOptions;	/* frame_clause options, see WindowDef */
+	ExprState  *startOffset;	/* expression for starting bound offset */
+	ExprState  *endOffset;		/* expression for ending bound offset */
+	Datum		startOffsetValue;	/* result of startOffset evaluation */
+	Datum		endOffsetValue; /* result of endOffset evaluation */
+
+	/* these fields are used with RANGE offset PRECEDING/FOLLOWING: */
+	FmgrInfo	startInRangeFunc;	/* in_range function for startOffset */
+	FmgrInfo	endInRangeFunc; /* in_range function for endOffset */
+	Oid			inRangeColl;	/* collation for in_range tests */
+	bool		inRangeAsc;		/* use ASC sort order for in_range tests? */
+	bool		inRangeNullsFirst;	/* nulls sort first for in_range tests? */
+
+	/* these fields are used in GROUPS mode: */
+	int64		currentgroup;	/* peer group # of current row in partition */
+	int64		frameheadgroup; /* peer group # of frame head row */
+	int64		frametailgroup; /* peer group # of frame tail row */
+	int64		groupheadpos;	/* current row's peer group head position */
+	int64		grouptailpos;	/* " " " " tail position (group end+1) */
+
+	MemoryContext partcontext;	/* context for partition-lifespan data */
+	MemoryContext aggcontext;	/* shared context for aggregate working data */
+	MemoryContext curaggcontext;	/* current aggregate's working data */
+	ExprContext *tmpcontext;	/* short-term evaluation context */
+
+	bool		all_first;		/* true if the scan is starting */
+	bool		all_done;		/* true if the scan is finished */
+	bool		partition_spooled;	/* true if all tuples in current partition
+									 * have been spooled into tuplestore */
+	bool		more_partitions;	/* true if there's more partitions after
+									 * this one */
+	bool		framehead_valid;	/* true if frameheadpos is known up to
+									 * date for current row */
+	bool		frametail_valid;	/* true if frametailpos is known up to
+									 * date for current row */
+	bool		grouptail_valid;	/* true if grouptailpos is known up to
+									 * date for current row */
+
+	TupleTableSlot *first_part_slot;	/* first tuple of current or next
+										 * partition */
+	TupleTableSlot *framehead_slot; /* first tuple of current frame */
+	TupleTableSlot *frametail_slot; /* first tuple after current frame */
+
+	/* temporary slots for tuples fetched back from tuplestore */
+	TupleTableSlot *agg_row_slot;
+	TupleTableSlot *temp_slot_1;
+	TupleTableSlot *temp_slot_2;
+} WindowAggState;
+
+/* ----------------
+ *	 UniqueState information
+ *
+ *		Unique nodes are used "on top of" sort nodes to discard
+ *		duplicate tuples returned from the sort phase.  Basically
+ *		all it does is compare the current tuple from the subplan
+ *		with the previously fetched tuple (stored in its result slot).
+ *		If the two are identical in all interesting fields, then
+ *		we just fetch another tuple from the sort and try again.
+ * ----------------
+ */
+typedef struct UniqueState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	ExprState  *eqfunction;		/* tuple equality qual */
+} UniqueState;
+
+/* ----------------
+ * GatherState information
+ *
+ *		Gather nodes launch 1 or more parallel workers, run a subplan
+ *		in those workers, and collect the results.
+ * ----------------
+ */
+typedef struct GatherState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	bool		initialized;	/* workers launched? */
+	bool		need_to_scan_locally;	/* need to read from local plan? */
+	int64		tuples_needed;	/* tuple bound, see ExecSetTupleBound */
+	/* these fields are set up once: */
+	TupleTableSlot *funnel_slot;
+	struct ParallelExecutorInfo *pei;
+	/* all remaining fields are reinitialized during a rescan: */
+	int			nworkers_launched;	/* original number of workers */
+	int			nreaders;		/* number of still-active workers */
+	int			nextreader;		/* next one to try to read from */
+	struct TupleQueueReader **reader;	/* array with nreaders active entries */
+} GatherState;
+
+/* ----------------
+ * GatherMergeState information
+ *
+ *		Gather merge nodes launch 1 or more parallel workers, run a
+ *		subplan which produces sorted output in each worker, and then
+ *		merge the results into a single sorted stream.
+ * ----------------
+ */
+struct GMReaderTupleBuffer;		/* private in nodeGatherMerge.c */
+
+typedef struct GatherMergeState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	bool		initialized;	/* workers launched? */
+	bool		gm_initialized; /* gather_merge_init() done? */
+	bool		need_to_scan_locally;	/* need to read from local plan? */
+	int64		tuples_needed;	/* tuple bound, see ExecSetTupleBound */
+	/* these fields are set up once: */
+	TupleDesc	tupDesc;		/* descriptor for subplan result tuples */
+	int			gm_nkeys;		/* number of sort columns */
+	SortSupport gm_sortkeys;	/* array of length gm_nkeys */
+	struct ParallelExecutorInfo *pei;
+	/* all remaining fields are reinitialized during a rescan */
+	/* (but the arrays are not reallocated, just cleared) */
+	int			nworkers_launched;	/* original number of workers */
+	int			nreaders;		/* number of active workers */
+	TupleTableSlot **gm_slots;	/* array with nreaders+1 entries */
+	struct TupleQueueReader **reader;	/* array with nreaders active entries */
+	struct GMReaderTupleBuffer *gm_tuple_buffers;	/* nreaders tuple buffers */
+	struct binaryheap *gm_heap; /* binary heap of slot indices */
+} GatherMergeState;
+
+/* ----------------
+ *	 Values displayed by EXPLAIN ANALYZE
+ * ----------------
+ */
+typedef struct HashInstrumentation
+{
+	int			nbuckets;		/* number of buckets at end of execution */
+	int			nbuckets_original;	/* planned number of buckets */
+	int			nbatch;			/* number of batches at end of execution */
+	int			nbatch_original;	/* planned number of batches */
+	Size		space_peak;		/* peak memory usage in bytes */
+} HashInstrumentation;
+
+/* ----------------
+ *	 Shared memory container for per-worker hash information
+ * ----------------
+ */
+typedef struct SharedHashInfo
+{
+	int			num_workers;
+	HashInstrumentation hinstrument[FLEXIBLE_ARRAY_MEMBER];
+} SharedHashInfo;
+
+/* ----------------
+ *	 HashState information
+ * ----------------
+ */
+typedef struct HashState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	HashJoinTable hashtable;	/* hash table for the hashjoin */
+	List	   *hashkeys;		/* list of ExprState nodes */
+
+	/*
+	 * In a parallelized hash join, the leader retains a pointer to the
+	 * shared-memory stats area in its shared_info field, and then copies the
+	 * shared-memory info back to local storage before DSM shutdown.  The
+	 * shared_info field remains NULL in workers, or in non-parallel joins.
+	 */
+	SharedHashInfo *shared_info;
+
+	/*
+	 * If we are collecting hash stats, this points to an initially-zeroed
+	 * collection area, which could be either local storage or in shared
+	 * memory; either way it's for just one process.
+	 */
+	HashInstrumentation *hinstrument;
+
+	/* Parallel hash state. */
+	struct ParallelHashJoinState *parallel_state;
+} HashState;
+
+/* ----------------
+ *	 SetOpState information
+ *
+ *		Even in "sorted" mode, SetOp nodes are more complex than a simple
+ *		Unique, since we have to count how many duplicates to return.  But
+ *		we also support hashing, so this is really more like a cut-down
+ *		form of Agg.
+ * ----------------
+ */
+/* this struct is private in nodeSetOp.c: */
+typedef struct SetOpStatePerGroupData *SetOpStatePerGroup;
+
+typedef struct SetOpState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	ExprState  *eqfunction;		/* equality comparator */
+	Oid		   *eqfuncoids;		/* per-grouping-field equality fns */
+	FmgrInfo   *hashfunctions;	/* per-grouping-field hash fns */
+	bool		setop_done;		/* indicates completion of output scan */
+	long		numOutput;		/* number of dups left to output */
+	/* these fields are used in SETOP_SORTED mode: */
+	SetOpStatePerGroup pergroup;	/* per-group working state */
+	HeapTuple	grp_firstTuple; /* copy of first tuple of current group */
+	/* these fields are used in SETOP_HASHED mode: */
+	TupleHashTable hashtable;	/* hash table with one entry per group */
+	MemoryContext tableContext; /* memory context containing hash table */
+	bool		table_filled;	/* hash table filled yet? */
+	TupleHashIterator hashiter; /* for iterating through hash table */
+} SetOpState;
+
+/* ----------------
+ *	 LockRowsState information
+ *
+ *		LockRows nodes are used to enforce FOR [KEY] UPDATE/SHARE locking.
+ * ----------------
+ */
+typedef struct LockRowsState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	List	   *lr_arowMarks;	/* List of ExecAuxRowMarks */
+	EPQState	lr_epqstate;	/* for evaluating EvalPlanQual rechecks */
+} LockRowsState;
+
+/* ----------------
+ *	 LimitState information
+ *
+ *		Limit nodes are used to enforce LIMIT/OFFSET clauses.
+ *		They just select the desired subrange of their subplan's output.
+ *
+ * offset is the number of initial tuples to skip (0 does nothing).
+ * count is the number of tuples to return after skipping the offset tuples.
+ * If no limit count was specified, count is undefined and noCount is true.
+ * When lstate == LIMIT_INITIAL, offset/count/noCount haven't been set yet.
+ * ----------------
+ */
+typedef enum
+{
+	LIMIT_INITIAL,				/* initial state for LIMIT node */
+	LIMIT_RESCAN,				/* rescan after recomputing parameters */
+	LIMIT_EMPTY,				/* there are no returnable rows */
+	LIMIT_INWINDOW,				/* have returned a row in the window */
+	LIMIT_WINDOWEND_TIES,		/* have returned a tied row */
+	LIMIT_SUBPLANEOF,			/* at EOF of subplan (within window) */
+	LIMIT_WINDOWEND,			/* stepped off end of window */
+	LIMIT_WINDOWSTART			/* stepped off beginning of window */
+} LimitStateCond;
+
+typedef struct LimitState
+{
+	PlanState	ps;				/* its first field is NodeTag */
+	ExprState  *limitOffset;	/* OFFSET parameter, or NULL if none */
+	ExprState  *limitCount;		/* COUNT parameter, or NULL if none */
+	LimitOption limitOption;	/* limit specification type */
+	int64		offset;			/* current OFFSET value */
+	int64		count;			/* current COUNT, if any */
+	bool		noCount;		/* if true, ignore count */
+	LimitStateCond lstate;		/* state machine status, as above */
+	int64		position;		/* 1-based index of last tuple returned */
+	TupleTableSlot *subSlot;	/* tuple last obtained from subplan */
+	ExprState  *eqfunction;		/* tuple equality qual in case of WITH TIES
+								 * option */
+	TupleTableSlot *last_slot;	/* slot for evaluation of ties */
+} LimitState;
+
+#endif							/* EXECNODES_H */
diff --git a/src/include/nodes/extensible.h b/src/include/nodes/extensible.h
new file mode 100644
index 0000000..d7bf0ba
--- /dev/null
+++ b/src/include/nodes/extensible.h
@@ -0,0 +1,160 @@
+/*-------------------------------------------------------------------------
+ *
+ * extensible.h
+ *	  Definitions for extensible nodes and custom scans
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/extensible.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef EXTENSIBLE_H
+#define EXTENSIBLE_H
+
+#include "access/parallel.h"
+#include "commands/explain.h"
+#include "nodes/execnodes.h"
+#include "nodes/pathnodes.h"
+#include "nodes/plannodes.h"
+
+/* maximum length of an extensible node identifier */
+#define EXTNODENAME_MAX_LEN					64
+
+/*
+ * An extensible node is a new type of node defined by an extension.  The
+ * type is always T_ExtensibleNode, while the extnodename identifies the
+ * specific type of node.  extnodename can be looked up to find the
+ * ExtensibleNodeMethods for this node type.
+ */
+typedef struct ExtensibleNode
+{
+	NodeTag		type;
+	const char *extnodename;	/* identifier of ExtensibleNodeMethods */
+} ExtensibleNode;
+
+/*
+ * node_size is the size of an extensible node of this type in bytes.
+ *
+ * nodeCopy is a function which performs a deep copy from oldnode to newnode.
+ * It does not need to copy type or extnodename, which are copied by the
+ * core system.
+ *
+ * nodeEqual is a function which performs a deep equality comparison between
+ * a and b and returns true or false accordingly.  It does not need to compare
+ * type or extnodename, which are compared by the core system.
+ *
+ * nodeOut is a serialization function for the node type.  It should use the
+ * output conventions typical for outfuncs.c.  It does not need to output
+ * type or extnodename; the core system handles those.
+ *
+ * nodeRead is a deserialization function for the node type.  It does not need
+ * to read type or extnodename; the core system handles those.  It should fetch
+ * the next token using pg_strtok() from the current input stream, and then
+ * reconstruct the private fields according to the manner in readfuncs.c.
+ *
+ * All callbacks are mandatory.
+ */
+typedef struct ExtensibleNodeMethods
+{
+	const char *extnodename;
+	Size		node_size;
+	void		(*nodeCopy) (struct ExtensibleNode *newnode,
+							 const struct ExtensibleNode *oldnode);
+	bool		(*nodeEqual) (const struct ExtensibleNode *a,
+							  const struct ExtensibleNode *b);
+	void		(*nodeOut) (struct StringInfoData *str,
+							const struct ExtensibleNode *node);
+	void		(*nodeRead) (struct ExtensibleNode *node);
+} ExtensibleNodeMethods;
+
+extern void RegisterExtensibleNodeMethods(const ExtensibleNodeMethods *method);
+extern const ExtensibleNodeMethods *GetExtensibleNodeMethods(const char *name,
+															 bool missing_ok);
+
+/*
+ * Flags for custom paths, indicating what capabilities the resulting scan
+ * will have.
+ */
+#define CUSTOMPATH_SUPPORT_BACKWARD_SCAN	0x0001
+#define CUSTOMPATH_SUPPORT_MARK_RESTORE		0x0002
+
+/*
+ * Custom path methods.  Mostly, we just need to know how to convert a
+ * CustomPath to a plan.
+ */
+typedef struct CustomPathMethods
+{
+	const char *CustomName;
+
+	/* Convert Path to a Plan */
+	struct Plan *(*PlanCustomPath) (PlannerInfo *root,
+									RelOptInfo *rel,
+									struct CustomPath *best_path,
+									List *tlist,
+									List *clauses,
+									List *custom_plans);
+	struct List *(*ReparameterizeCustomPathByChild) (PlannerInfo *root,
+													 List *custom_private,
+													 RelOptInfo *child_rel);
+}			CustomPathMethods;
+
+/*
+ * Custom scan.  Here again, there's not much to do: we need to be able to
+ * generate a ScanState corresponding to the scan.
+ */
+typedef struct CustomScanMethods
+{
+	const char *CustomName;
+
+	/* Create execution state (CustomScanState) from a CustomScan plan node */
+	Node	   *(*CreateCustomScanState) (CustomScan *cscan);
+} CustomScanMethods;
+
+/*
+ * Execution-time methods for a CustomScanState.  This is more complex than
+ * what we need for a custom path or scan.
+ */
+typedef struct CustomExecMethods
+{
+	const char *CustomName;
+
+	/* Required executor methods */
+	void		(*BeginCustomScan) (CustomScanState *node,
+									EState *estate,
+									int eflags);
+	TupleTableSlot *(*ExecCustomScan) (CustomScanState *node);
+	void		(*EndCustomScan) (CustomScanState *node);
+	void		(*ReScanCustomScan) (CustomScanState *node);
+
+	/* Optional methods: needed if mark/restore is supported */
+	void		(*MarkPosCustomScan) (CustomScanState *node);
+	void		(*RestrPosCustomScan) (CustomScanState *node);
+
+	/* Optional methods: needed if parallel execution is supported */
+	Size		(*EstimateDSMCustomScan) (CustomScanState *node,
+										  ParallelContext *pcxt);
+	void		(*InitializeDSMCustomScan) (CustomScanState *node,
+											ParallelContext *pcxt,
+											void *coordinate);
+	void		(*ReInitializeDSMCustomScan) (CustomScanState *node,
+											  ParallelContext *pcxt,
+											  void *coordinate);
+	void		(*InitializeWorkerCustomScan) (CustomScanState *node,
+											   shm_toc *toc,
+											   void *coordinate);
+	void		(*ShutdownCustomScan) (CustomScanState *node);
+
+	/* Optional: print additional information in EXPLAIN */
+	void		(*ExplainCustomScan) (CustomScanState *node,
+									  List *ancestors,
+									  ExplainState *es);
+} CustomExecMethods;
+
+extern void RegisterCustomScanMethods(const CustomScanMethods *methods);
+extern const CustomScanMethods *GetCustomScanMethods(const char *CustomName,
+													 bool missing_ok);
+
+#endif							/* EXTENSIBLE_H */
diff --git a/src/include/nodes/lockoptions.h b/src/include/nodes/lockoptions.h
new file mode 100644
index 0000000..56dfe32
--- /dev/null
+++ b/src/include/nodes/lockoptions.h
@@ -0,0 +1,61 @@
+/*-------------------------------------------------------------------------
+ *
+ * lockoptions.h
+ *	  Common header for some locking-related declarations.
+ *
+ *
+ * Copyright (c) 2014-2020, PostgreSQL Global Development Group
+ *
+ * src/include/nodes/lockoptions.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef LOCKOPTIONS_H
+#define LOCKOPTIONS_H
+
+/*
+ * This enum represents the different strengths of FOR UPDATE/SHARE clauses.
+ * The ordering here is important, because the highest numerical value takes
+ * precedence when a RTE is specified multiple ways.  See applyLockingClause.
+ */
+typedef enum LockClauseStrength
+{
+	LCS_NONE,					/* no such clause - only used in PlanRowMark */
+	LCS_FORKEYSHARE,			/* FOR KEY SHARE */
+	LCS_FORSHARE,				/* FOR SHARE */
+	LCS_FORNOKEYUPDATE,			/* FOR NO KEY UPDATE */
+	LCS_FORUPDATE				/* FOR UPDATE */
+} LockClauseStrength;
+
+/*
+ * This enum controls how to deal with rows being locked by FOR UPDATE/SHARE
+ * clauses (i.e., it represents the NOWAIT and SKIP LOCKED options).
+ * The ordering here is important, because the highest numerical value takes
+ * precedence when a RTE is specified multiple ways.  See applyLockingClause.
+ */
+typedef enum LockWaitPolicy
+{
+	/* Wait for the lock to become available (default behavior) */
+	LockWaitBlock,
+	/* Skip rows that can't be locked (SKIP LOCKED) */
+	LockWaitSkip,
+	/* Raise an error if a row cannot be locked (NOWAIT) */
+	LockWaitError
+} LockWaitPolicy;
+
+/*
+ * Possible lock modes for a tuple.
+ */
+typedef enum LockTupleMode
+{
+	/* SELECT FOR KEY SHARE */
+	LockTupleKeyShare,
+	/* SELECT FOR SHARE */
+	LockTupleShare,
+	/* SELECT FOR NO KEY UPDATE, and UPDATEs that don't modify key columns */
+	LockTupleNoKeyExclusive,
+	/* SELECT FOR UPDATE, UPDATEs that modify key columns, and DELETE */
+	LockTupleExclusive
+} LockTupleMode;
+
+#endif							/* LOCKOPTIONS_H */
diff --git a/src/include/nodes/makefuncs.h b/src/include/nodes/makefuncs.h
new file mode 100644
index 0000000..31d9aed
--- /dev/null
+++ b/src/include/nodes/makefuncs.h
@@ -0,0 +1,108 @@
+/*-------------------------------------------------------------------------
+ *
+ * makefuncs.h
+ *	  prototypes for the creator functions of various nodes
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/makefuncs.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef MAKEFUNC_H
+#define MAKEFUNC_H
+
+#include "nodes/execnodes.h"
+#include "nodes/parsenodes.h"
+
+
+extern A_Expr *makeA_Expr(A_Expr_Kind kind, List *name,
+						  Node *lexpr, Node *rexpr, int location);
+
+extern A_Expr *makeSimpleA_Expr(A_Expr_Kind kind, char *name,
+								Node *lexpr, Node *rexpr, int location);
+
+extern Var *makeVar(Index varno,
+					AttrNumber varattno,
+					Oid vartype,
+					int32 vartypmod,
+					Oid varcollid,
+					Index varlevelsup);
+
+extern Var *makeVarFromTargetEntry(Index varno,
+								   TargetEntry *tle);
+
+extern Var *makeWholeRowVar(RangeTblEntry *rte,
+							Index varno,
+							Index varlevelsup,
+							bool allowScalar);
+
+extern TargetEntry *makeTargetEntry(Expr *expr,
+									AttrNumber resno,
+									char *resname,
+									bool resjunk);
+
+extern TargetEntry *flatCopyTargetEntry(TargetEntry *src_tle);
+
+extern FromExpr *makeFromExpr(List *fromlist, Node *quals);
+
+extern Const *makeConst(Oid consttype,
+						int32 consttypmod,
+						Oid constcollid,
+						int constlen,
+						Datum constvalue,
+						bool constisnull,
+						bool constbyval);
+
+extern Const *makeNullConst(Oid consttype, int32 consttypmod, Oid constcollid);
+
+extern Node *makeBoolConst(bool value, bool isnull);
+
+extern Expr *makeBoolExpr(BoolExprType boolop, List *args, int location);
+
+extern Alias *makeAlias(const char *aliasname, List *colnames);
+
+extern RelabelType *makeRelabelType(Expr *arg, Oid rtype, int32 rtypmod,
+									Oid rcollid, CoercionForm rformat);
+
+extern RangeVar *makeRangeVar(char *schemaname, char *relname, int location);
+
+extern TypeName *makeTypeName(char *typnam);
+extern TypeName *makeTypeNameFromNameList(List *names);
+extern TypeName *makeTypeNameFromOid(Oid typeOid, int32 typmod);
+
+extern ColumnDef *makeColumnDef(const char *colname,
+								Oid typeOid, int32 typmod, Oid collOid);
+
+extern FuncExpr *makeFuncExpr(Oid funcid, Oid rettype, List *args,
+							  Oid funccollid, Oid inputcollid, CoercionForm fformat);
+
+extern FuncCall *makeFuncCall(List *name, List *args, int location);
+
+extern Expr *make_opclause(Oid opno, Oid opresulttype, bool opretset,
+						   Expr *leftop, Expr *rightop,
+						   Oid opcollid, Oid inputcollid);
+
+extern Expr *make_andclause(List *andclauses);
+extern Expr *make_orclause(List *orclauses);
+extern Expr *make_notclause(Expr *notclause);
+
+extern Node *make_and_qual(Node *qual1, Node *qual2);
+extern Expr *make_ands_explicit(List *andclauses);
+extern List *make_ands_implicit(Expr *clause);
+
+extern IndexInfo *makeIndexInfo(int numattrs, int numkeyattrs, Oid amoid,
+								List *expressions, List *predicates,
+								bool unique, bool isready, bool concurrent);
+
+extern DefElem *makeDefElem(char *name, Node *arg, int location);
+extern DefElem *makeDefElemExtended(char *nameSpace, char *name, Node *arg,
+									DefElemAction defaction, int location);
+
+extern GroupingSet *makeGroupingSet(GroupingSetKind kind, List *content, int location);
+
+extern VacuumRelation *makeVacuumRelation(RangeVar *relation, Oid oid, List *va_cols);
+
+#endif							/* MAKEFUNC_H */
diff --git a/src/include/nodes/memnodes.h b/src/include/nodes/memnodes.h
new file mode 100644
index 0000000..c9f2bbc
--- /dev/null
+++ b/src/include/nodes/memnodes.h
@@ -0,0 +1,108 @@
+/*-------------------------------------------------------------------------
+ *
+ * memnodes.h
+ *	  POSTGRES memory context node definitions.
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/memnodes.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef MEMNODES_H
+#define MEMNODES_H
+
+#include "nodes/nodes.h"
+
+/*
+ * MemoryContextCounters
+ *		Summarization state for MemoryContextStats collection.
+ *
+ * The set of counters in this struct is biased towards AllocSet; if we ever
+ * add any context types that are based on fundamentally different approaches,
+ * we might need more or different counters here.  A possible API spec then
+ * would be to print only nonzero counters, but for now we just summarize in
+ * the format historically used by AllocSet.
+ */
+typedef struct MemoryContextCounters
+{
+	Size		nblocks;		/* Total number of malloc blocks */
+	Size		freechunks;		/* Total number of free chunks */
+	Size		totalspace;		/* Total bytes requested from malloc */
+	Size		freespace;		/* The unused portion of totalspace */
+} MemoryContextCounters;
+
+/*
+ * MemoryContext
+ *		A logical context in which memory allocations occur.
+ *
+ * MemoryContext itself is an abstract type that can have multiple
+ * implementations.
+ * The function pointers in MemoryContextMethods define one specific
+ * implementation of MemoryContext --- they are a virtual function table
+ * in C++ terms.
+ *
+ * Node types that are actual implementations of memory contexts must
+ * begin with the same fields as MemoryContextData.
+ *
+ * Note: for largely historical reasons, typedef MemoryContext is a pointer
+ * to the context struct rather than the struct type itself.
+ */
+
+typedef void (*MemoryStatsPrintFunc) (MemoryContext context, void *passthru,
+									  const char *stats_string);
+
+typedef struct MemoryContextMethods
+{
+	void	   *(*alloc) (MemoryContext context, Size size);
+	/* call this free_p in case someone #define's free() */
+	void		(*free_p) (MemoryContext context, void *pointer);
+	void	   *(*realloc) (MemoryContext context, void *pointer, Size size);
+	void		(*reset) (MemoryContext context);
+	void		(*delete_context) (MemoryContext context);
+	Size		(*get_chunk_space) (MemoryContext context, void *pointer);
+	bool		(*is_empty) (MemoryContext context);
+	void		(*stats) (MemoryContext context,
+						  MemoryStatsPrintFunc printfunc, void *passthru,
+						  MemoryContextCounters *totals);
+#ifdef MEMORY_CONTEXT_CHECKING
+	void		(*check) (MemoryContext context);
+#endif
+} MemoryContextMethods;
+
+
+typedef struct MemoryContextData
+{
+	NodeTag		type;			/* identifies exact kind of context */
+	/* these two fields are placed here to minimize alignment wastage: */
+	bool		isReset;		/* T = no space alloced since last reset */
+	bool		allowInCritSection; /* allow palloc in critical section */
+	Size		mem_allocated;	/* track memory allocated for this context */
+	const MemoryContextMethods *methods;	/* virtual function table */
+	MemoryContext parent;		/* NULL if no parent (toplevel context) */
+	MemoryContext firstchild;	/* head of linked list of children */
+	MemoryContext prevchild;	/* previous child of same parent */
+	MemoryContext nextchild;	/* next child of same parent */
+	const char *name;			/* context name (just for debugging) */
+	const char *ident;			/* context ID if any (just for debugging) */
+	MemoryContextCallback *reset_cbs;	/* list of reset/delete callbacks */
+} MemoryContextData;
+
+/* utils/palloc.h contains typedef struct MemoryContextData *MemoryContext */
+
+
+/*
+ * MemoryContextIsValid
+ *		True iff memory context is valid.
+ *
+ * Add new context types to the set accepted by this macro.
+ */
+#define MemoryContextIsValid(context) \
+	((context) != NULL && \
+	 (IsA((context), AllocSetContext) || \
+	  IsA((context), SlabContext) || \
+	  IsA((context), GenerationContext)))
+
+#endif							/* MEMNODES_H */
diff --git a/src/include/nodes/nodeFuncs.h b/src/include/nodes/nodeFuncs.h
new file mode 100644
index 0000000..9cc56ee
--- /dev/null
+++ b/src/include/nodes/nodeFuncs.h
@@ -0,0 +1,162 @@
+/*-------------------------------------------------------------------------
+ *
+ * nodeFuncs.h
+ *		Various general-purpose manipulations of Node trees
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/nodeFuncs.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef NODEFUNCS_H
+#define NODEFUNCS_H
+
+#include "nodes/parsenodes.h"
+
+
+/* flags bits for query_tree_walker and query_tree_mutator */
+#define QTW_IGNORE_RT_SUBQUERIES	0x01	/* subqueries in rtable */
+#define QTW_IGNORE_CTE_SUBQUERIES	0x02	/* subqueries in cteList */
+#define QTW_IGNORE_RC_SUBQUERIES	0x03	/* both of above */
+#define QTW_IGNORE_JOINALIASES		0x04	/* JOIN alias var lists */
+#define QTW_IGNORE_RANGE_TABLE		0x08	/* skip rangetable entirely */
+#define QTW_EXAMINE_RTES_BEFORE		0x10	/* examine RTE nodes before their
+											 * contents */
+#define QTW_EXAMINE_RTES_AFTER		0x20	/* examine RTE nodes after their
+											 * contents */
+#define QTW_DONT_COPY_QUERY			0x40	/* do not copy top Query */
+#define QTW_EXAMINE_SORTGROUP		0x80	/* include SortGroupNode lists */
+
+/* callback function for check_functions_in_node */
+typedef bool (*check_function_callback) (Oid func_id, void *context);
+
+
+extern Oid	exprType(const Node *expr);
+extern int32 exprTypmod(const Node *expr);
+extern bool exprIsLengthCoercion(const Node *expr, int32 *coercedTypmod);
+extern Node *applyRelabelType(Node *arg, Oid rtype, int32 rtypmod, Oid rcollid,
+							  CoercionForm rformat, int rlocation,
+							  bool overwrite_ok);
+extern Node *relabel_to_typmod(Node *expr, int32 typmod);
+extern Node *strip_implicit_coercions(Node *node);
+extern bool expression_returns_set(Node *clause);
+
+extern Oid	exprCollation(const Node *expr);
+extern Oid	exprInputCollation(const Node *expr);
+extern void exprSetCollation(Node *expr, Oid collation);
+extern void exprSetInputCollation(Node *expr, Oid inputcollation);
+
+extern int	exprLocation(const Node *expr);
+
+extern void fix_opfuncids(Node *node);
+extern void set_opfuncid(OpExpr *opexpr);
+extern void set_sa_opfuncid(ScalarArrayOpExpr *opexpr);
+
+/* Is clause a FuncExpr clause? */
+static inline bool
+is_funcclause(const void *clause)
+{
+	return clause != NULL && IsA(clause, FuncExpr);
+}
+
+/* Is clause an OpExpr clause? */
+static inline bool
+is_opclause(const void *clause)
+{
+	return clause != NULL && IsA(clause, OpExpr);
+}
+
+/* Extract left arg of a binary opclause, or only arg of a unary opclause */
+static inline Node *
+get_leftop(const void *clause)
+{
+	const OpExpr *expr = (const OpExpr *) clause;
+
+	if (expr->args != NIL)
+		return (Node *) linitial(expr->args);
+	else
+		return NULL;
+}
+
+/* Extract right arg of a binary opclause (NULL if it's a unary opclause) */
+static inline Node *
+get_rightop(const void *clause)
+{
+	const OpExpr *expr = (const OpExpr *) clause;
+
+	if (list_length(expr->args) >= 2)
+		return (Node *) lsecond(expr->args);
+	else
+		return NULL;
+}
+
+/* Is clause an AND clause? */
+static inline bool
+is_andclause(const void *clause)
+{
+	return (clause != NULL &&
+			IsA(clause, BoolExpr) &&
+			((const BoolExpr *) clause)->boolop == AND_EXPR);
+}
+
+/* Is clause an OR clause? */
+static inline bool
+is_orclause(const void *clause)
+{
+	return (clause != NULL &&
+			IsA(clause, BoolExpr) &&
+			((const BoolExpr *) clause)->boolop == OR_EXPR);
+}
+
+/* Is clause a NOT clause? */
+static inline bool
+is_notclause(const void *clause)
+{
+	return (clause != NULL &&
+			IsA(clause, BoolExpr) &&
+			((const BoolExpr *) clause)->boolop == NOT_EXPR);
+}
+
+/* Extract argument from a clause known to be a NOT clause */
+static inline Expr *
+get_notclausearg(const void *notclause)
+{
+	return (Expr *) linitial(((const BoolExpr *) notclause)->args);
+}
+
+extern bool check_functions_in_node(Node *node, check_function_callback checker,
+									void *context);
+
+extern bool expression_tree_walker(Node *node, bool (*walker) (),
+								   void *context);
+extern Node *expression_tree_mutator(Node *node, Node *(*mutator) (),
+									 void *context);
+
+extern bool query_tree_walker(Query *query, bool (*walker) (),
+							  void *context, int flags);
+extern Query *query_tree_mutator(Query *query, Node *(*mutator) (),
+								 void *context, int flags);
+
+extern bool range_table_walker(List *rtable, bool (*walker) (),
+							   void *context, int flags);
+extern List *range_table_mutator(List *rtable, Node *(*mutator) (),
+								 void *context, int flags);
+
+extern bool range_table_entry_walker(RangeTblEntry *rte, bool (*walker) (),
+									 void *context, int flags);
+
+extern bool query_or_expression_tree_walker(Node *node, bool (*walker) (),
+											void *context, int flags);
+extern Node *query_or_expression_tree_mutator(Node *node, Node *(*mutator) (),
+											  void *context, int flags);
+
+extern bool raw_expression_tree_walker(Node *node, bool (*walker) (),
+									   void *context);
+
+struct PlanState;
+extern bool planstate_tree_walker(struct PlanState *planstate, bool (*walker) (),
+								  void *context);
+
+#endif							/* NODEFUNCS_H */
diff --git a/src/include/nodes/nodes.h b/src/include/nodes/nodes.h
new file mode 100644
index 0000000..381d84b
--- /dev/null
+++ b/src/include/nodes/nodes.h
@@ -0,0 +1,842 @@
+/*-------------------------------------------------------------------------
+ *
+ * nodes.h
+ *	  Definitions for tagged nodes.
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/nodes.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef NODES_H
+#define NODES_H
+
+/*
+ * The first field of every node is NodeTag. Each node created (with makeNode)
+ * will have one of the following tags as the value of its first field.
+ *
+ * Note that inserting or deleting node types changes the numbers of other
+ * node types later in the list.  This is no problem during development, since
+ * the node numbers are never stored on disk.  But don't do it in a released
+ * branch, because that would represent an ABI break for extensions.
+ */
+typedef enum NodeTag
+{
+	T_Invalid = 0,
+
+	/*
+	 * TAGS FOR EXECUTOR NODES (execnodes.h)
+	 */
+	T_IndexInfo,
+	T_ExprContext,
+	T_ProjectionInfo,
+	T_JunkFilter,
+	T_OnConflictSetState,
+	T_ResultRelInfo,
+	T_EState,
+	T_TupleTableSlot,
+
+	/*
+	 * TAGS FOR PLAN NODES (plannodes.h)
+	 */
+	T_Plan,
+	T_Result,
+	T_ProjectSet,
+	T_ModifyTable,
+	T_Append,
+	T_MergeAppend,
+	T_RecursiveUnion,
+	T_BitmapAnd,
+	T_BitmapOr,
+	T_Scan,
+	T_SeqScan,
+	T_SampleScan,
+	T_IndexScan,
+	T_IndexOnlyScan,
+	T_BitmapIndexScan,
+	T_BitmapHeapScan,
+	T_TidScan,
+	T_SubqueryScan,
+	T_FunctionScan,
+	T_ValuesScan,
+	T_TableFuncScan,
+	T_CteScan,
+	T_NamedTuplestoreScan,
+	T_WorkTableScan,
+	T_ForeignScan,
+	T_CustomScan,
+	T_Join,
+	T_NestLoop,
+	T_MergeJoin,
+	T_HashJoin,
+	T_Material,
+	T_Sort,
+	T_IncrementalSort,
+	T_Group,
+	T_Agg,
+	T_WindowAgg,
+	T_Unique,
+	T_Gather,
+	T_GatherMerge,
+	T_Hash,
+	T_SetOp,
+	T_LockRows,
+	T_Limit,
+	/* these aren't subclasses of Plan: */
+	T_NestLoopParam,
+	T_PlanRowMark,
+	T_PartitionPruneInfo,
+	T_PartitionedRelPruneInfo,
+	T_PartitionPruneStepOp,
+	T_PartitionPruneStepCombine,
+	T_PlanInvalItem,
+
+	/*
+	 * TAGS FOR PLAN STATE NODES (execnodes.h)
+	 *
+	 * These should correspond one-to-one with Plan node types.
+	 */
+	T_PlanState,
+	T_ResultState,
+	T_ProjectSetState,
+	T_ModifyTableState,
+	T_AppendState,
+	T_MergeAppendState,
+	T_RecursiveUnionState,
+	T_BitmapAndState,
+	T_BitmapOrState,
+	T_ScanState,
+	T_SeqScanState,
+	T_SampleScanState,
+	T_IndexScanState,
+	T_IndexOnlyScanState,
+	T_BitmapIndexScanState,
+	T_BitmapHeapScanState,
+	T_TidScanState,
+	T_SubqueryScanState,
+	T_FunctionScanState,
+	T_TableFuncScanState,
+	T_ValuesScanState,
+	T_CteScanState,
+	T_NamedTuplestoreScanState,
+	T_WorkTableScanState,
+	T_ForeignScanState,
+	T_CustomScanState,
+	T_JoinState,
+	T_NestLoopState,
+	T_MergeJoinState,
+	T_HashJoinState,
+	T_MaterialState,
+	T_SortState,
+	T_IncrementalSortState,
+	T_GroupState,
+	T_AggState,
+	T_WindowAggState,
+	T_UniqueState,
+	T_GatherState,
+	T_GatherMergeState,
+	T_HashState,
+	T_SetOpState,
+	T_LockRowsState,
+	T_LimitState,
+
+	/*
+	 * TAGS FOR PRIMITIVE NODES (primnodes.h)
+	 */
+	T_Alias,
+	T_RangeVar,
+	T_TableFunc,
+	T_Expr,
+	T_Var,
+	T_Const,
+	T_Param,
+	T_Aggref,
+	T_GroupingFunc,
+	T_WindowFunc,
+	T_SubscriptingRef,
+	T_FuncExpr,
+	T_NamedArgExpr,
+	T_OpExpr,
+	T_DistinctExpr,
+	T_NullIfExpr,
+	T_ScalarArrayOpExpr,
+	T_BoolExpr,
+	T_SubLink,
+	T_SubPlan,
+	T_AlternativeSubPlan,
+	T_FieldSelect,
+	T_FieldStore,
+	T_RelabelType,
+	T_CoerceViaIO,
+	T_ArrayCoerceExpr,
+	T_ConvertRowtypeExpr,
+	T_CollateExpr,
+	T_CaseExpr,
+	T_CaseWhen,
+	T_CaseTestExpr,
+	T_ArrayExpr,
+	T_RowExpr,
+	T_RowCompareExpr,
+	T_CoalesceExpr,
+	T_MinMaxExpr,
+	T_SQLValueFunction,
+	T_XmlExpr,
+	T_NullTest,
+	T_BooleanTest,
+	T_CoerceToDomain,
+	T_CoerceToDomainValue,
+	T_SetToDefault,
+	T_CurrentOfExpr,
+	T_NextValueExpr,
+	T_InferenceElem,
+	T_TargetEntry,
+	T_RangeTblRef,
+	T_JoinExpr,
+	T_FromExpr,
+	T_OnConflictExpr,
+	T_IntoClause,
+
+	/*
+	 * TAGS FOR EXPRESSION STATE NODES (execnodes.h)
+	 *
+	 * ExprState represents the evaluation state for a whole expression tree.
+	 * Most Expr-based plan nodes do not have a corresponding expression state
+	 * node, they're fully handled within execExpr* - but sometimes the state
+	 * needs to be shared with other parts of the executor, as for example
+	 * with AggrefExprState, which nodeAgg.c has to modify.
+	 */
+	T_ExprState,
+	T_AggrefExprState,
+	T_WindowFuncExprState,
+	T_SetExprState,
+	T_SubPlanState,
+	T_AlternativeSubPlanState,
+	T_DomainConstraintState,
+
+	/*
+	 * TAGS FOR PLANNER NODES (pathnodes.h)
+	 */
+	T_PlannerInfo,
+	T_PlannerGlobal,
+	T_RelOptInfo,
+	T_IndexOptInfo,
+	T_ForeignKeyOptInfo,
+	T_ParamPathInfo,
+	T_Path,
+	T_IndexPath,
+	T_BitmapHeapPath,
+	T_BitmapAndPath,
+	T_BitmapOrPath,
+	T_TidPath,
+	T_SubqueryScanPath,
+	T_ForeignPath,
+	T_CustomPath,
+	T_NestPath,
+	T_MergePath,
+	T_HashPath,
+	T_AppendPath,
+	T_MergeAppendPath,
+	T_GroupResultPath,
+	T_MaterialPath,
+	T_UniquePath,
+	T_GatherPath,
+	T_GatherMergePath,
+	T_ProjectionPath,
+	T_ProjectSetPath,
+	T_SortPath,
+	T_IncrementalSortPath,
+	T_GroupPath,
+	T_UpperUniquePath,
+	T_AggPath,
+	T_GroupingSetsPath,
+	T_MinMaxAggPath,
+	T_WindowAggPath,
+	T_SetOpPath,
+	T_RecursiveUnionPath,
+	T_LockRowsPath,
+	T_ModifyTablePath,
+	T_LimitPath,
+	/* these aren't subclasses of Path: */
+	T_EquivalenceClass,
+	T_EquivalenceMember,
+	T_PathKey,
+	T_PathTarget,
+	T_RestrictInfo,
+	T_IndexClause,
+	T_PlaceHolderVar,
+	T_SpecialJoinInfo,
+	T_AppendRelInfo,
+	T_PlaceHolderInfo,
+	T_MinMaxAggInfo,
+	T_PlannerParamItem,
+	T_RollupData,
+	T_GroupingSetData,
+	T_StatisticExtInfo,
+
+	/*
+	 * TAGS FOR MEMORY NODES (memnodes.h)
+	 */
+	T_MemoryContext,
+	T_AllocSetContext,
+	T_SlabContext,
+	T_GenerationContext,
+
+	/*
+	 * TAGS FOR VALUE NODES (value.h)
+	 */
+	T_Value,
+	T_Integer,
+	T_Float,
+	T_String,
+	T_BitString,
+	T_Null,
+
+	/*
+	 * TAGS FOR LIST NODES (pg_list.h)
+	 */
+	T_List,
+	T_IntList,
+	T_OidList,
+
+	/*
+	 * TAGS FOR EXTENSIBLE NODES (extensible.h)
+	 */
+	T_ExtensibleNode,
+
+	/*
+	 * TAGS FOR STATEMENT NODES (mostly in parsenodes.h)
+	 */
+	T_RawStmt,
+	T_Query,
+	T_PlannedStmt,
+	T_InsertStmt,
+	T_DeleteStmt,
+	T_UpdateStmt,
+	T_SelectStmt,
+	T_AlterTableStmt,
+	T_AlterTableCmd,
+	T_AlterDomainStmt,
+	T_SetOperationStmt,
+	T_GrantStmt,
+	T_GrantRoleStmt,
+	T_AlterDefaultPrivilegesStmt,
+	T_ClosePortalStmt,
+	T_ClusterStmt,
+	T_CopyStmt,
+	T_CreateStmt,
+	T_DefineStmt,
+	T_DropStmt,
+	T_TruncateStmt,
+	T_CommentStmt,
+	T_FetchStmt,
+	T_IndexStmt,
+	T_CreateFunctionStmt,
+	T_AlterFunctionStmt,
+	T_DoStmt,
+	T_RenameStmt,
+	T_RuleStmt,
+	T_NotifyStmt,
+	T_ListenStmt,
+	T_UnlistenStmt,
+	T_TransactionStmt,
+	T_ViewStmt,
+	T_LoadStmt,
+	T_CreateDomainStmt,
+	T_CreatedbStmt,
+	T_DropdbStmt,
+	T_VacuumStmt,
+	T_ExplainStmt,
+	T_CreateTableAsStmt,
+	T_CreateSeqStmt,
+	T_AlterSeqStmt,
+	T_VariableSetStmt,
+	T_VariableShowStmt,
+	T_DiscardStmt,
+	T_CreateTrigStmt,
+	T_CreatePLangStmt,
+	T_CreateRoleStmt,
+	T_AlterRoleStmt,
+	T_DropRoleStmt,
+	T_LockStmt,
+	T_ConstraintsSetStmt,
+	T_ReindexStmt,
+	T_CheckPointStmt,
+	T_CreateSchemaStmt,
+	T_AlterDatabaseStmt,
+	T_AlterDatabaseSetStmt,
+	T_AlterRoleSetStmt,
+	T_CreateConversionStmt,
+	T_CreateCastStmt,
+	T_CreateOpClassStmt,
+	T_CreateOpFamilyStmt,
+	T_AlterOpFamilyStmt,
+	T_PrepareStmt,
+	T_ExecuteStmt,
+	T_DeallocateStmt,
+	T_DeclareCursorStmt,
+	T_CreateTableSpaceStmt,
+	T_DropTableSpaceStmt,
+	T_AlterObjectDependsStmt,
+	T_AlterObjectSchemaStmt,
+	T_AlterOwnerStmt,
+	T_AlterOperatorStmt,
+	T_AlterTypeStmt,
+	T_DropOwnedStmt,
+	T_ReassignOwnedStmt,
+	T_CompositeTypeStmt,
+	T_CreateEnumStmt,
+	T_CreateRangeStmt,
+	T_AlterEnumStmt,
+	T_AlterTSDictionaryStmt,
+	T_AlterTSConfigurationStmt,
+	T_CreateFdwStmt,
+	T_AlterFdwStmt,
+	T_CreateForeignServerStmt,
+	T_AlterForeignServerStmt,
+	T_CreateUserMappingStmt,
+	T_AlterUserMappingStmt,
+	T_DropUserMappingStmt,
+	T_AlterTableSpaceOptionsStmt,
+	T_AlterTableMoveAllStmt,
+	T_SecLabelStmt,
+	T_CreateForeignTableStmt,
+	T_ImportForeignSchemaStmt,
+	T_CreateExtensionStmt,
+	T_AlterExtensionStmt,
+	T_AlterExtensionContentsStmt,
+	T_CreateEventTrigStmt,
+	T_AlterEventTrigStmt,
+	T_RefreshMatViewStmt,
+	T_ReplicaIdentityStmt,
+	T_AlterSystemStmt,
+	T_CreatePolicyStmt,
+	T_AlterPolicyStmt,
+	T_CreateTransformStmt,
+	T_CreateAmStmt,
+	T_CreatePublicationStmt,
+	T_AlterPublicationStmt,
+	T_CreateSubscriptionStmt,
+	T_AlterSubscriptionStmt,
+	T_DropSubscriptionStmt,
+	T_CreateStatsStmt,
+	T_AlterCollationStmt,
+	T_CallStmt,
+	T_AlterStatsStmt,
+
+	/*
+	 * TAGS FOR PARSE TREE NODES (parsenodes.h)
+	 */
+	T_A_Expr,
+	T_ColumnRef,
+	T_ParamRef,
+	T_A_Const,
+	T_FuncCall,
+	T_A_Star,
+	T_A_Indices,
+	T_A_Indirection,
+	T_A_ArrayExpr,
+	T_ResTarget,
+	T_MultiAssignRef,
+	T_TypeCast,
+	T_CollateClause,
+	T_SortBy,
+	T_WindowDef,
+	T_RangeSubselect,
+	T_RangeFunction,
+	T_RangeTableSample,
+	T_RangeTableFunc,
+	T_RangeTableFuncCol,
+	T_TypeName,
+	T_ColumnDef,
+	T_IndexElem,
+	T_Constraint,
+	T_DefElem,
+	T_RangeTblEntry,
+	T_RangeTblFunction,
+	T_TableSampleClause,
+	T_WithCheckOption,
+	T_SortGroupClause,
+	T_GroupingSet,
+	T_WindowClause,
+	T_ObjectWithArgs,
+	T_AccessPriv,
+	T_CreateOpClassItem,
+	T_TableLikeClause,
+	T_FunctionParameter,
+	T_LockingClause,
+	T_RowMarkClause,
+	T_XmlSerialize,
+	T_WithClause,
+	T_InferClause,
+	T_OnConflictClause,
+	T_CommonTableExpr,
+	T_RoleSpec,
+	T_TriggerTransition,
+	T_PartitionElem,
+	T_PartitionSpec,
+	T_PartitionBoundSpec,
+	T_PartitionRangeDatum,
+	T_PartitionCmd,
+	T_VacuumRelation,
+
+	/*
+	 * TAGS FOR REPLICATION GRAMMAR PARSE NODES (replnodes.h)
+	 */
+	T_IdentifySystemCmd,
+	T_BaseBackupCmd,
+	T_CreateReplicationSlotCmd,
+	T_DropReplicationSlotCmd,
+	T_StartReplicationCmd,
+	T_TimeLineHistoryCmd,
+	T_SQLCmd,
+
+	/*
+	 * TAGS FOR RANDOM OTHER STUFF
+	 *
+	 * These are objects that aren't part of parse/plan/execute node tree
+	 * structures, but we give them NodeTags anyway for identification
+	 * purposes (usually because they are involved in APIs where we want to
+	 * pass multiple object types through the same pointer).
+	 */
+	T_TriggerData,				/* in commands/trigger.h */
+	T_EventTriggerData,			/* in commands/event_trigger.h */
+	T_ReturnSetInfo,			/* in nodes/execnodes.h */
+	T_WindowObjectData,			/* private in nodeWindowAgg.c */
+	T_TIDBitmap,				/* in nodes/tidbitmap.h */
+	T_InlineCodeBlock,			/* in nodes/parsenodes.h */
+	T_FdwRoutine,				/* in foreign/fdwapi.h */
+	T_IndexAmRoutine,			/* in access/amapi.h */
+	T_TableAmRoutine,			/* in access/tableam.h */
+	T_TsmRoutine,				/* in access/tsmapi.h */
+	T_ForeignKeyCacheInfo,		/* in utils/rel.h */
+	T_CallContext,				/* in nodes/parsenodes.h */
+	T_SupportRequestSimplify,	/* in nodes/supportnodes.h */
+	T_SupportRequestSelectivity,	/* in nodes/supportnodes.h */
+	T_SupportRequestCost,		/* in nodes/supportnodes.h */
+	T_SupportRequestRows,		/* in nodes/supportnodes.h */
+	T_SupportRequestIndexCondition	/* in nodes/supportnodes.h */
+} NodeTag;
+
+/*
+ * The first field of a node of any type is guaranteed to be the NodeTag.
+ * Hence the type of any node can be gotten by casting it to Node. Declaring
+ * a variable to be of Node * (instead of void *) can also facilitate
+ * debugging.
+ */
+typedef struct Node
+{
+	NodeTag		type;
+} Node;
+
+#define nodeTag(nodeptr)		(((const Node*)(nodeptr))->type)
+
+/*
+ * newNode -
+ *	  create a new node of the specified size and tag the node with the
+ *	  specified tag.
+ *
+ * !WARNING!: Avoid using newNode directly. You should be using the
+ *	  macro makeNode.  eg. to create a Query node, use makeNode(Query)
+ *
+ * Note: the size argument should always be a compile-time constant, so the
+ * apparent risk of multiple evaluation doesn't matter in practice.
+ */
+#ifdef __GNUC__
+
+/* With GCC, we can use a compound statement within an expression */
+#define newNode(size, tag) \
+({	Node   *_result; \
+	AssertMacro((size) >= sizeof(Node));		/* need the tag, at least */ \
+	_result = (Node *) palloc0fast(size); \
+	_result->type = (tag); \
+	_result; \
+})
+#else
+
+/*
+ *	There is no way to dereference the palloc'ed pointer to assign the
+ *	tag, and also return the pointer itself, so we need a holder variable.
+ *	Fortunately, this macro isn't recursive so we just define
+ *	a global variable for this purpose.
+ */
+extern PGDLLIMPORT Node *newNodeMacroHolder;
+
+#define newNode(size, tag) \
+( \
+	AssertMacro((size) >= sizeof(Node)),		/* need the tag, at least */ \
+	newNodeMacroHolder = (Node *) palloc0fast(size), \
+	newNodeMacroHolder->type = (tag), \
+	newNodeMacroHolder \
+)
+#endif							/* __GNUC__ */
+
+
+#define makeNode(_type_)		((_type_ *) newNode(sizeof(_type_),T_##_type_))
+#define NodeSetTag(nodeptr,t)	(((Node*)(nodeptr))->type = (t))
+
+#define IsA(nodeptr,_type_)		(nodeTag(nodeptr) == T_##_type_)
+
+/*
+ * castNode(type, ptr) casts ptr to "type *", and if assertions are enabled,
+ * verifies that the node has the appropriate type (using its nodeTag()).
+ *
+ * Use an inline function when assertions are enabled, to avoid multiple
+ * evaluations of the ptr argument (which could e.g. be a function call).
+ */
+#ifdef USE_ASSERT_CHECKING
+static inline Node *
+castNodeImpl(NodeTag type, void *ptr)
+{
+	Assert(ptr == NULL || nodeTag(ptr) == type);
+	return (Node *) ptr;
+}
+#define castNode(_type_, nodeptr) ((_type_ *) castNodeImpl(T_##_type_, nodeptr))
+#else
+#define castNode(_type_, nodeptr) ((_type_ *) (nodeptr))
+#endif							/* USE_ASSERT_CHECKING */
+
+
+/* ----------------------------------------------------------------
+ *					  extern declarations follow
+ * ----------------------------------------------------------------
+ */
+
+/*
+ * nodes/{outfuncs.c,print.c}
+ */
+struct Bitmapset;				/* not to include bitmapset.h here */
+struct StringInfoData;			/* not to include stringinfo.h here */
+
+extern void outNode(struct StringInfoData *str, const void *obj);
+extern void outToken(struct StringInfoData *str, const char *s);
+extern void outBitmapset(struct StringInfoData *str,
+						 const struct Bitmapset *bms);
+extern void outDatum(struct StringInfoData *str, uintptr_t value,
+					 int typlen, bool typbyval);
+extern char *nodeToString(const void *obj);
+extern char *bmsToString(const struct Bitmapset *bms);
+
+/*
+ * nodes/{readfuncs.c,read.c}
+ */
+extern void *stringToNode(const char *str);
+#ifdef WRITE_READ_PARSE_PLAN_TREES
+extern void *stringToNodeWithLocations(const char *str);
+#endif
+extern struct Bitmapset *readBitmapset(void);
+extern uintptr_t readDatum(bool typbyval);
+extern bool *readBoolCols(int numCols);
+extern int *readIntCols(int numCols);
+extern Oid *readOidCols(int numCols);
+extern int16 *readAttrNumberCols(int numCols);
+
+/*
+ * nodes/copyfuncs.c
+ */
+extern void *copyObjectImpl(const void *obj);
+
+/* cast result back to argument type, if supported by compiler */
+#ifdef HAVE_TYPEOF
+#define copyObject(obj) ((typeof(obj)) copyObjectImpl(obj))
+#else
+#define copyObject(obj) copyObjectImpl(obj)
+#endif
+
+/*
+ * nodes/equalfuncs.c
+ */
+extern bool equal(const void *a, const void *b);
+
+
+/*
+ * Typedefs for identifying qualifier selectivities and plan costs as such.
+ * These are just plain "double"s, but declaring a variable as Selectivity
+ * or Cost makes the intent more obvious.
+ *
+ * These could have gone into plannodes.h or some such, but many files
+ * depend on them...
+ */
+typedef double Selectivity;		/* fraction of tuples a qualifier will pass */
+typedef double Cost;			/* execution cost (in page-access units) */
+
+
+/*
+ * CmdType -
+ *	  enums for type of operation represented by a Query or PlannedStmt
+ *
+ * This is needed in both parsenodes.h and plannodes.h, so put it here...
+ */
+typedef enum CmdType
+{
+	CMD_UNKNOWN,
+	CMD_SELECT,					/* select stmt */
+	CMD_UPDATE,					/* update stmt */
+	CMD_INSERT,					/* insert stmt */
+	CMD_DELETE,
+	CMD_UTILITY,				/* cmds like create, destroy, copy, vacuum,
+								 * etc. */
+	CMD_NOTHING					/* dummy command for instead nothing rules
+								 * with qual */
+} CmdType;
+
+
+/*
+ * JoinType -
+ *	  enums for types of relation joins
+ *
+ * JoinType determines the exact semantics of joining two relations using
+ * a matching qualification.  For example, it tells what to do with a tuple
+ * that has no match in the other relation.
+ *
+ * This is needed in both parsenodes.h and plannodes.h, so put it here...
+ */
+typedef enum JoinType
+{
+	/*
+	 * The canonical kinds of joins according to the SQL JOIN syntax. Only
+	 * these codes can appear in parser output (e.g., JoinExpr nodes).
+	 */
+	JOIN_INNER,					/* matching tuple pairs only */
+	JOIN_LEFT,					/* pairs + unmatched LHS tuples */
+	JOIN_FULL,					/* pairs + unmatched LHS + unmatched RHS */
+	JOIN_RIGHT,					/* pairs + unmatched RHS tuples */
+
+	/*
+	 * Semijoins and anti-semijoins (as defined in relational theory) do not
+	 * appear in the SQL JOIN syntax, but there are standard idioms for
+	 * representing them (e.g., using EXISTS).  The planner recognizes these
+	 * cases and converts them to joins.  So the planner and executor must
+	 * support these codes.  NOTE: in JOIN_SEMI output, it is unspecified
+	 * which matching RHS row is joined to.  In JOIN_ANTI output, the row is
+	 * guaranteed to be null-extended.
+	 */
+	JOIN_SEMI,					/* 1 copy of each LHS row that has match(es) */
+	JOIN_ANTI,					/* 1 copy of each LHS row that has no match */
+
+	/*
+	 * These codes are used internally in the planner, but are not supported
+	 * by the executor (nor, indeed, by most of the planner).
+	 */
+	JOIN_UNIQUE_OUTER,			/* LHS path must be made unique */
+	JOIN_UNIQUE_INNER			/* RHS path must be made unique */
+
+	/*
+	 * We might need additional join types someday.
+	 */
+} JoinType;
+
+/*
+ * OUTER joins are those for which pushed-down quals must behave differently
+ * from the join's own quals.  This is in fact everything except INNER and
+ * SEMI joins.  However, this macro must also exclude the JOIN_UNIQUE symbols
+ * since those are temporary proxies for what will eventually be an INNER
+ * join.
+ *
+ * Note: semijoins are a hybrid case, but we choose to treat them as not
+ * being outer joins.  This is okay principally because the SQL syntax makes
+ * it impossible to have a pushed-down qual that refers to the inner relation
+ * of a semijoin; so there is no strong need to distinguish join quals from
+ * pushed-down quals.  This is convenient because for almost all purposes,
+ * quals attached to a semijoin can be treated the same as innerjoin quals.
+ */
+#define IS_OUTER_JOIN(jointype) \
+	(((1 << (jointype)) & \
+	  ((1 << JOIN_LEFT) | \
+	   (1 << JOIN_FULL) | \
+	   (1 << JOIN_RIGHT) | \
+	   (1 << JOIN_ANTI))) != 0)
+
+/*
+ * AggStrategy -
+ *	  overall execution strategies for Agg plan nodes
+ *
+ * This is needed in both pathnodes.h and plannodes.h, so put it here...
+ */
+typedef enum AggStrategy
+{
+	AGG_PLAIN,					/* simple agg across all input rows */
+	AGG_SORTED,					/* grouped agg, input must be sorted */
+	AGG_HASHED,					/* grouped agg, use internal hashtable */
+	AGG_MIXED					/* grouped agg, hash and sort both used */
+} AggStrategy;
+
+/*
+ * AggSplit -
+ *	  splitting (partial aggregation) modes for Agg plan nodes
+ *
+ * This is needed in both pathnodes.h and plannodes.h, so put it here...
+ */
+
+/* Primitive options supported by nodeAgg.c: */
+#define AGGSPLITOP_COMBINE		0x01	/* substitute combinefn for transfn */
+#define AGGSPLITOP_SKIPFINAL	0x02	/* skip finalfn, return state as-is */
+#define AGGSPLITOP_SERIALIZE	0x04	/* apply serialfn to output */
+#define AGGSPLITOP_DESERIALIZE	0x08	/* apply deserialfn to input */
+
+/* Supported operating modes (i.e., useful combinations of these options): */
+typedef enum AggSplit
+{
+	/* Basic, non-split aggregation: */
+	AGGSPLIT_SIMPLE = 0,
+	/* Initial phase of partial aggregation, with serialization: */
+	AGGSPLIT_INITIAL_SERIAL = AGGSPLITOP_SKIPFINAL | AGGSPLITOP_SERIALIZE,
+	/* Final phase of partial aggregation, with deserialization: */
+	AGGSPLIT_FINAL_DESERIAL = AGGSPLITOP_COMBINE | AGGSPLITOP_DESERIALIZE
+} AggSplit;
+
+/* Test whether an AggSplit value selects each primitive option: */
+#define DO_AGGSPLIT_COMBINE(as)		(((as) & AGGSPLITOP_COMBINE) != 0)
+#define DO_AGGSPLIT_SKIPFINAL(as)	(((as) & AGGSPLITOP_SKIPFINAL) != 0)
+#define DO_AGGSPLIT_SERIALIZE(as)	(((as) & AGGSPLITOP_SERIALIZE) != 0)
+#define DO_AGGSPLIT_DESERIALIZE(as) (((as) & AGGSPLITOP_DESERIALIZE) != 0)
+
+/*
+ * SetOpCmd and SetOpStrategy -
+ *	  overall semantics and execution strategies for SetOp plan nodes
+ *
+ * This is needed in both pathnodes.h and plannodes.h, so put it here...
+ */
+typedef enum SetOpCmd
+{
+	SETOPCMD_INTERSECT,
+	SETOPCMD_INTERSECT_ALL,
+	SETOPCMD_EXCEPT,
+	SETOPCMD_EXCEPT_ALL
+} SetOpCmd;
+
+typedef enum SetOpStrategy
+{
+	SETOP_SORTED,				/* input must be sorted */
+	SETOP_HASHED				/* use internal hashtable */
+} SetOpStrategy;
+
+/*
+ * OnConflictAction -
+ *	  "ON CONFLICT" clause type of query
+ *
+ * This is needed in both parsenodes.h and plannodes.h, so put it here...
+ */
+typedef enum OnConflictAction
+{
+	ONCONFLICT_NONE,			/* No "ON CONFLICT" clause */
+	ONCONFLICT_NOTHING,			/* ON CONFLICT ... DO NOTHING */
+	ONCONFLICT_UPDATE			/* ON CONFLICT ... DO UPDATE */
+} OnConflictAction;
+
+/*
+ * LimitOption -
+ *	LIMIT option of query
+ *
+ * This is needed in both parsenodes.h and plannodes.h, so put it here...
+ */
+typedef enum LimitOption
+{
+	LIMIT_OPTION_COUNT,			/* FETCH FIRST... ONLY */
+	LIMIT_OPTION_WITH_TIES,		/* FETCH FIRST... WITH TIES */
+	LIMIT_OPTION_DEFAULT,		/* No limit present */
+} LimitOption;
+
+#endif							/* NODES_H */
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
new file mode 100644
index 0000000..4898d90
--- /dev/null
+++ b/src/include/nodes/params.h
@@ -0,0 +1,170 @@
+/*-------------------------------------------------------------------------
+ *
+ * params.h
+ *	  Support for finding the values associated with Param nodes.
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/params.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef PARAMS_H
+#define PARAMS_H
+
+/* Forward declarations, to avoid including other headers */
+struct Bitmapset;
+struct ExprState;
+struct Param;
+struct ParseState;
+
+
+/*
+ *	  ParamListInfo
+ *
+ *	  ParamListInfo structures are used to pass parameters into the executor
+ *	  for parameterized plans.  We support two basic approaches to supplying
+ *	  parameter values, the "static" way and the "dynamic" way.
+ *
+ *	  In the static approach, per-parameter data is stored in an array of
+ *	  ParamExternData structs appended to the ParamListInfo struct.
+ *	  Each entry in the array defines the value to be substituted for a
+ *	  PARAM_EXTERN parameter.  The "paramid" of a PARAM_EXTERN Param
+ *	  can range from 1 to numParams.
+ *
+ *	  Although parameter numbers are normally consecutive, we allow
+ *	  ptype == InvalidOid to signal an unused array entry.
+ *
+ *	  pflags is a flags field.  Currently the only used bit is:
+ *	  PARAM_FLAG_CONST signals the planner that it may treat this parameter
+ *	  as a constant (i.e., generate a plan that works only for this value
+ *	  of the parameter).
+ *
+ *	  In the dynamic approach, all access to parameter values is done through
+ *	  hook functions found in the ParamListInfo struct.  In this case,
+ *	  the ParamExternData array is typically unused and not allocated;
+ *	  but the legal range of paramid is still 1 to numParams.
+ *
+ *	  Although the data structure is really an array, not a list, we keep
+ *	  the old typedef name to avoid unnecessary code changes.
+ *
+ *	  There are 3 hook functions that can be associated with a ParamListInfo
+ *	  structure:
+ *
+ *	  If paramFetch isn't null, it is called to fetch the ParamExternData
+ *	  for a particular param ID, rather than accessing the relevant element
+ *	  of the ParamExternData array.  This supports the case where the array
+ *	  isn't there at all, as well as cases where the data in the array
+ *	  might be obsolete or lazily evaluated.  paramFetch must return the
+ *	  address of a ParamExternData struct describing the specified param ID;
+ *	  the convention above about ptype == InvalidOid signaling an invalid
+ *	  param ID still applies.  The returned struct can either be placed in
+ *	  the "workspace" supplied by the caller, or it can be in storage
+ *	  controlled by the paramFetch hook if that's more convenient.
+ *	  (In either case, the struct is not expected to be long-lived.)
+ *	  If "speculative" is true, the paramFetch hook should not risk errors
+ *	  in trying to fetch the parameter value, and should report an invalid
+ *	  parameter instead.
+ *
+ *	  If paramCompile isn't null, then it controls what execExpr.c compiles
+ *	  for PARAM_EXTERN Param nodes --- typically, this hook would emit a
+ *	  EEOP_PARAM_CALLBACK step.  This allows unnecessary work to be
+ *	  optimized away in compiled expressions.
+ *
+ *	  If parserSetup isn't null, then it is called to re-instantiate the
+ *	  original parsing hooks when a query needs to be re-parsed/planned.
+ *	  This is especially useful if the types of parameters might change
+ *	  from time to time, since it can replace the need to supply a fixed
+ *	  list of parameter types to the parser.
+ *
+ *	  Notice that the paramFetch and paramCompile hooks are actually passed
+ *	  the ParamListInfo struct's address; they can therefore access all
+ *	  three of the "arg" fields, and the distinction between paramFetchArg
+ *	  and paramCompileArg is rather arbitrary.
+ */
+
+#define PARAM_FLAG_CONST	0x0001	/* parameter is constant */
+
+typedef struct ParamExternData
+{
+	Datum		value;			/* parameter value */
+	bool		isnull;			/* is it NULL? */
+	uint16		pflags;			/* flag bits, see above */
+	Oid			ptype;			/* parameter's datatype, or 0 */
+} ParamExternData;
+
+typedef struct ParamListInfoData *ParamListInfo;
+
+typedef ParamExternData *(*ParamFetchHook) (ParamListInfo params,
+											int paramid, bool speculative,
+											ParamExternData *workspace);
+
+typedef void (*ParamCompileHook) (ParamListInfo params, struct Param *param,
+								  struct ExprState *state,
+								  Datum *resv, bool *resnull);
+
+typedef void (*ParserSetupHook) (struct ParseState *pstate, void *arg);
+
+typedef struct ParamListInfoData
+{
+	ParamFetchHook paramFetch;	/* parameter fetch hook */
+	void	   *paramFetchArg;
+	ParamCompileHook paramCompile;	/* parameter compile hook */
+	void	   *paramCompileArg;
+	ParserSetupHook parserSetup;	/* parser setup hook */
+	void	   *parserSetupArg;
+	char	   *paramValuesStr; /* params as a single string for errors */
+	int			numParams;		/* nominal/maximum # of Params represented */
+
+	/*
+	 * params[] may be of length zero if paramFetch is supplied; otherwise it
+	 * must be of length numParams.
+	 */
+	ParamExternData params[FLEXIBLE_ARRAY_MEMBER];
+}			ParamListInfoData;
+
+
+/* ----------------
+ *	  ParamExecData
+ *
+ *	  ParamExecData entries are used for executor internal parameters
+ *	  (that is, values being passed into or out of a sub-query).  The
+ *	  paramid of a PARAM_EXEC Param is a (zero-based) index into an
+ *	  array of ParamExecData records, which is referenced through
+ *	  es_param_exec_vals or ecxt_param_exec_vals.
+ *
+ *	  If execPlan is not NULL, it points to a SubPlanState node that needs
+ *	  to be executed to produce the value.  (This is done so that we can have
+ *	  lazy evaluation of InitPlans: they aren't executed until/unless a
+ *	  result value is needed.)	Otherwise the value is assumed to be valid
+ *	  when needed.
+ * ----------------
+ */
+
+typedef struct ParamExecData
+{
+	void	   *execPlan;		/* should be "SubPlanState *" */
+	Datum		value;
+	bool		isnull;
+} ParamExecData;
+
+/* type of argument for ParamsErrorCallback */
+typedef struct ParamsErrorCbData
+{
+	const char *portalName;
+	ParamListInfo params;
+} ParamsErrorCbData;
+
+/* Functions found in src/backend/nodes/params.c */
+extern ParamListInfo makeParamList(int numParams);
+extern ParamListInfo copyParamList(ParamListInfo from);
+extern Size EstimateParamListSpace(ParamListInfo paramLI);
+extern void SerializeParamList(ParamListInfo paramLI, char **start_address);
+extern ParamListInfo RestoreParamList(char **start_address);
+extern char *BuildParamLogString(ParamListInfo params, char **paramTextValues,
+								 int valueLen);
+extern void ParamsErrorCallback(void *arg);
+
+#endif							/* PARAMS_H */
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
new file mode 100644
index 0000000..557074c
--- /dev/null
+++ b/src/include/nodes/parsenodes.h
@@ -0,0 +1,3579 @@
+/*-------------------------------------------------------------------------
+ *
+ * parsenodes.h
+ *	  definitions for parse tree nodes
+ *
+ * Many of the node types used in parsetrees include a "location" field.
+ * This is a byte (not character) offset in the original source text, to be
+ * used for positioning an error cursor when there is an error related to
+ * the node.  Access to the original source text is needed to make use of
+ * the location.  At the topmost (statement) level, we also provide a
+ * statement length, likewise measured in bytes, for convenience in
+ * identifying statement boundaries in multi-statement source strings.
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/parsenodes.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef PARSENODES_H
+#define PARSENODES_H
+
+#include "nodes/bitmapset.h"
+#include "nodes/lockoptions.h"
+#include "nodes/primnodes.h"
+#include "nodes/value.h"
+#include "partitioning/partdefs.h"
+
+
+typedef enum OverridingKind
+{
+	OVERRIDING_NOT_SET = 0,
+	OVERRIDING_USER_VALUE,
+	OVERRIDING_SYSTEM_VALUE
+} OverridingKind;
+
+/* Possible sources of a Query */
+typedef enum QuerySource
+{
+	QSRC_ORIGINAL,				/* original parsetree (explicit query) */
+	QSRC_PARSER,				/* added by parse analysis (now unused) */
+	QSRC_INSTEAD_RULE,			/* added by unconditional INSTEAD rule */
+	QSRC_QUAL_INSTEAD_RULE,		/* added by conditional INSTEAD rule */
+	QSRC_NON_INSTEAD_RULE		/* added by non-INSTEAD rule */
+} QuerySource;
+
+/* Sort ordering options for ORDER BY and CREATE INDEX */
+typedef enum SortByDir
+{
+	SORTBY_DEFAULT,
+	SORTBY_ASC,
+	SORTBY_DESC,
+	SORTBY_USING				/* not allowed in CREATE INDEX ... */
+} SortByDir;
+
+typedef enum SortByNulls
+{
+	SORTBY_NULLS_DEFAULT,
+	SORTBY_NULLS_FIRST,
+	SORTBY_NULLS_LAST
+} SortByNulls;
+
+/*
+ * Grantable rights are encoded so that we can OR them together in a bitmask.
+ * The present representation of AclItem limits us to 16 distinct rights,
+ * even though AclMode is defined as uint32.  See utils/acl.h.
+ *
+ * Caution: changing these codes breaks stored ACLs, hence forces initdb.
+ */
+typedef uint32 AclMode;			/* a bitmask of privilege bits */
+
+#define ACL_INSERT		(1<<0)	/* for relations */
+#define ACL_SELECT		(1<<1)
+#define ACL_UPDATE		(1<<2)
+#define ACL_DELETE		(1<<3)
+#define ACL_TRUNCATE	(1<<4)
+#define ACL_REFERENCES	(1<<5)
+#define ACL_TRIGGER		(1<<6)
+#define ACL_EXECUTE		(1<<7)	/* for functions */
+#define ACL_USAGE		(1<<8)	/* for languages, namespaces, FDWs, and
+								 * servers */
+#define ACL_CREATE		(1<<9)	/* for namespaces and databases */
+#define ACL_CREATE_TEMP (1<<10) /* for databases */
+#define ACL_CONNECT		(1<<11) /* for databases */
+#define N_ACL_RIGHTS	12		/* 1 plus the last 1<<x */
+#define ACL_NO_RIGHTS	0
+/* Currently, SELECT ... FOR [KEY] UPDATE/SHARE requires UPDATE privileges */
+#define ACL_SELECT_FOR_UPDATE	ACL_UPDATE
+
+
+/*****************************************************************************
+ *	Query Tree
+ *****************************************************************************/
+
+/*
+ * Query -
+ *	  Parse analysis turns all statements into a Query tree
+ *	  for further processing by the rewriter and planner.
+ *
+ *	  Utility statements (i.e. non-optimizable statements) have the
+ *	  utilityStmt field set, and the rest of the Query is mostly dummy.
+ *
+ *	  Planning converts a Query tree into a Plan tree headed by a PlannedStmt
+ *	  node --- the Query structure is not used by the executor.
+ */
+typedef struct Query
+{
+	NodeTag		type;
+
+	CmdType		commandType;	/* select|insert|update|delete|utility */
+
+	QuerySource querySource;	/* where did I come from? */
+
+	uint64		queryId;		/* query identifier (can be set by plugins) */
+
+	bool		canSetTag;		/* do I set the command result tag? */
+
+	Node	   *utilityStmt;	/* non-null if commandType == CMD_UTILITY */
+
+	int			resultRelation; /* rtable index of target relation for
+								 * INSERT/UPDATE/DELETE; 0 for SELECT */
+
+	bool		hasAggs;		/* has aggregates in tlist or havingQual */
+	bool		hasWindowFuncs; /* has window functions in tlist */
+	bool		hasTargetSRFs;	/* has set-returning functions in tlist */
+	bool		hasSubLinks;	/* has subquery SubLink */
+	bool		hasDistinctOn;	/* distinctClause is from DISTINCT ON */
+	bool		hasRecursive;	/* WITH RECURSIVE was specified */
+	bool		hasModifyingCTE;	/* has INSERT/UPDATE/DELETE in WITH */
+	bool		hasForUpdate;	/* FOR [KEY] UPDATE/SHARE was specified */
+	bool		hasRowSecurity; /* rewriter has applied some RLS policy */
+
+	List	   *cteList;		/* WITH list (of CommonTableExpr's) */
+
+	List	   *rtable;			/* list of range table entries */
+	FromExpr   *jointree;		/* table join tree (FROM and WHERE clauses) */
+
+	List	   *targetList;		/* target list (of TargetEntry) */
+
+	OverridingKind override;	/* OVERRIDING clause */
+
+	OnConflictExpr *onConflict; /* ON CONFLICT DO [NOTHING | UPDATE] */
+
+	List	   *returningList;	/* return-values list (of TargetEntry) */
+
+	List	   *groupClause;	/* a list of SortGroupClause's */
+
+	List	   *groupingSets;	/* a list of GroupingSet's if present */
+
+	Node	   *havingQual;		/* qualifications applied to groups */
+
+	List	   *windowClause;	/* a list of WindowClause's */
+
+	List	   *distinctClause; /* a list of SortGroupClause's */
+
+	List	   *sortClause;		/* a list of SortGroupClause's */
+
+	Node	   *limitOffset;	/* # of result tuples to skip (int8 expr) */
+	Node	   *limitCount;		/* # of result tuples to return (int8 expr) */
+	LimitOption limitOption;	/* limit type */
+
+	List	   *rowMarks;		/* a list of RowMarkClause's */
+
+	Node	   *setOperations;	/* set-operation tree if this is top level of
+								 * a UNION/INTERSECT/EXCEPT query */
+
+	List	   *constraintDeps; /* a list of pg_constraint OIDs that the query
+								 * depends on to be semantically valid */
+
+	List	   *withCheckOptions;	/* a list of WithCheckOption's (added
+									 * during rewrite) */
+
+	/*
+	 * The following two fields identify the portion of the source text string
+	 * containing this query.  They are typically only populated in top-level
+	 * Queries, not in sub-queries.  When not set, they might both be zero, or
+	 * both be -1 meaning "unknown".
+	 */
+	int			stmt_location;	/* start location, or -1 if unknown */
+	int			stmt_len;		/* length in bytes; 0 means "rest of string" */
+} Query;
+
+
+/****************************************************************************
+ *	Supporting data structures for Parse Trees
+ *
+ *	Most of these node types appear in raw parsetrees output by the grammar,
+ *	and get transformed to something else by the analyzer.  A few of them
+ *	are used as-is in transformed querytrees.
+ ****************************************************************************/
+
+/*
+ * TypeName - specifies a type in definitions
+ *
+ * For TypeName structures generated internally, it is often easier to
+ * specify the type by OID than by name.  If "names" is NIL then the
+ * actual type OID is given by typeOid, otherwise typeOid is unused.
+ * Similarly, if "typmods" is NIL then the actual typmod is expected to
+ * be prespecified in typemod, otherwise typemod is unused.
+ *
+ * If pct_type is true, then names is actually a field name and we look up
+ * the type of that field.  Otherwise (the normal case), names is a type
+ * name possibly qualified with schema and database name.
+ */
+typedef struct TypeName
+{
+	NodeTag		type;
+	List	   *names;			/* qualified name (list of Value strings) */
+	Oid			typeOid;		/* type identified by OID */
+	bool		setof;			/* is a set? */
+	bool		pct_type;		/* %TYPE specified? */
+	List	   *typmods;		/* type modifier expression(s) */
+	int32		typemod;		/* prespecified type modifier */
+	List	   *arrayBounds;	/* array bounds */
+	int			location;		/* token location, or -1 if unknown */
+} TypeName;
+
+/*
+ * ColumnRef - specifies a reference to a column, or possibly a whole tuple
+ *
+ * The "fields" list must be nonempty.  It can contain string Value nodes
+ * (representing names) and A_Star nodes (representing occurrence of a '*').
+ * Currently, A_Star must appear only as the last list element --- the grammar
+ * is responsible for enforcing this!
+ *
+ * Note: any container subscripting or selection of fields from composite columns
+ * is represented by an A_Indirection node above the ColumnRef.  However,
+ * for simplicity in the normal case, initial field selection from a table
+ * name is represented within ColumnRef and not by adding A_Indirection.
+ */
+typedef struct ColumnRef
+{
+	NodeTag		type;
+	List	   *fields;			/* field names (Value strings) or A_Star */
+	int			location;		/* token location, or -1 if unknown */
+} ColumnRef;
+
+/*
+ * ParamRef - specifies a $n parameter reference
+ */
+typedef struct ParamRef
+{
+	NodeTag		type;
+	int			number;			/* the number of the parameter */
+	int			location;		/* token location, or -1 if unknown */
+} ParamRef;
+
+/*
+ * A_Expr - infix, prefix, and postfix expressions
+ */
+typedef enum A_Expr_Kind
+{
+	AEXPR_OP,					/* normal operator */
+	AEXPR_OP_ANY,				/* scalar op ANY (array) */
+	AEXPR_OP_ALL,				/* scalar op ALL (array) */
+	AEXPR_DISTINCT,				/* IS DISTINCT FROM - name must be "=" */
+	AEXPR_NOT_DISTINCT,			/* IS NOT DISTINCT FROM - name must be "=" */
+	AEXPR_NULLIF,				/* NULLIF - name must be "=" */
+	AEXPR_OF,					/* IS [NOT] OF - name must be "=" or "<>" */
+	AEXPR_IN,					/* [NOT] IN - name must be "=" or "<>" */
+	AEXPR_LIKE,					/* [NOT] LIKE - name must be "~~" or "!~~" */
+	AEXPR_ILIKE,				/* [NOT] ILIKE - name must be "~~*" or "!~~*" */
+	AEXPR_SIMILAR,				/* [NOT] SIMILAR - name must be "~" or "!~" */
+	AEXPR_BETWEEN,				/* name must be "BETWEEN" */
+	AEXPR_NOT_BETWEEN,			/* name must be "NOT BETWEEN" */
+	AEXPR_BETWEEN_SYM,			/* name must be "BETWEEN SYMMETRIC" */
+	AEXPR_NOT_BETWEEN_SYM,		/* name must be "NOT BETWEEN SYMMETRIC" */
+	AEXPR_PAREN					/* nameless dummy node for parentheses */
+} A_Expr_Kind;
+
+typedef struct A_Expr
+{
+	NodeTag		type;
+	A_Expr_Kind kind;			/* see above */
+	List	   *name;			/* possibly-qualified name of operator */
+	Node	   *lexpr;			/* left argument, or NULL if none */
+	Node	   *rexpr;			/* right argument, or NULL if none */
+	int			location;		/* token location, or -1 if unknown */
+} A_Expr;
+
+/*
+ * A_Const - a literal constant
+ */
+typedef struct A_Const
+{
+	NodeTag		type;
+	Value		val;			/* value (includes type info, see value.h) */
+	int			location;		/* token location, or -1 if unknown */
+} A_Const;
+
+/*
+ * TypeCast - a CAST expression
+ */
+typedef struct TypeCast
+{
+	NodeTag		type;
+	Node	   *arg;			/* the expression being casted */
+	TypeName   *typeName;		/* the target type */
+	int			location;		/* token location, or -1 if unknown */
+} TypeCast;
+
+/*
+ * CollateClause - a COLLATE expression
+ */
+typedef struct CollateClause
+{
+	NodeTag		type;
+	Node	   *arg;			/* input expression */
+	List	   *collname;		/* possibly-qualified collation name */
+	int			location;		/* token location, or -1 if unknown */
+} CollateClause;
+
+/*
+ * RoleSpec - a role name or one of a few special values.
+ */
+typedef enum RoleSpecType
+{
+	ROLESPEC_CSTRING,			/* role name is stored as a C string */
+	ROLESPEC_CURRENT_USER,		/* role spec is CURRENT_USER */
+	ROLESPEC_SESSION_USER,		/* role spec is SESSION_USER */
+	ROLESPEC_PUBLIC				/* role name is "public" */
+} RoleSpecType;
+
+typedef struct RoleSpec
+{
+	NodeTag		type;
+	RoleSpecType roletype;		/* Type of this rolespec */
+	char	   *rolename;		/* filled only for ROLESPEC_CSTRING */
+	int			location;		/* token location, or -1 if unknown */
+} RoleSpec;
+
+/*
+ * FuncCall - a function or aggregate invocation
+ *
+ * agg_order (if not NIL) indicates we saw 'foo(... ORDER BY ...)', or if
+ * agg_within_group is true, it was 'foo(...) WITHIN GROUP (ORDER BY ...)'.
+ * agg_star indicates we saw a 'foo(*)' construct, while agg_distinct
+ * indicates we saw 'foo(DISTINCT ...)'.  In any of these cases, the
+ * construct *must* be an aggregate call.  Otherwise, it might be either an
+ * aggregate or some other kind of function.  However, if FILTER or OVER is
+ * present it had better be an aggregate or window function.
+ *
+ * Normally, you'd initialize this via makeFuncCall() and then only change the
+ * parts of the struct its defaults don't match afterwards, as needed.
+ */
+typedef struct FuncCall
+{
+	NodeTag		type;
+	List	   *funcname;		/* qualified name of function */
+	List	   *args;			/* the arguments (list of exprs) */
+	List	   *agg_order;		/* ORDER BY (list of SortBy) */
+	Node	   *agg_filter;		/* FILTER clause, if any */
+	bool		agg_within_group;	/* ORDER BY appeared in WITHIN GROUP */
+	bool		agg_star;		/* argument was really '*' */
+	bool		agg_distinct;	/* arguments were labeled DISTINCT */
+	bool		func_variadic;	/* last argument was labeled VARIADIC */
+	struct WindowDef *over;		/* OVER clause, if any */
+	int			location;		/* token location, or -1 if unknown */
+} FuncCall;
+
+/*
+ * A_Star - '*' representing all columns of a table or compound field
+ *
+ * This can appear within ColumnRef.fields, A_Indirection.indirection, and
+ * ResTarget.indirection lists.
+ */
+typedef struct A_Star
+{
+	NodeTag		type;
+} A_Star;
+
+/*
+ * A_Indices - array subscript or slice bounds ([idx] or [lidx:uidx])
+ *
+ * In slice case, either or both of lidx and uidx can be NULL (omitted).
+ * In non-slice case, uidx holds the single subscript and lidx is always NULL.
+ */
+typedef struct A_Indices
+{
+	NodeTag		type;
+	bool		is_slice;		/* true if slice (i.e., colon present) */
+	Node	   *lidx;			/* slice lower bound, if any */
+	Node	   *uidx;			/* subscript, or slice upper bound if any */
+} A_Indices;
+
+/*
+ * A_Indirection - select a field and/or array element from an expression
+ *
+ * The indirection list can contain A_Indices nodes (representing
+ * subscripting), string Value nodes (representing field selection --- the
+ * string value is the name of the field to select), and A_Star nodes
+ * (representing selection of all fields of a composite type).
+ * For example, a complex selection operation like
+ *				(foo).field1[42][7].field2
+ * would be represented with a single A_Indirection node having a 4-element
+ * indirection list.
+ *
+ * Currently, A_Star must appear only as the last list element --- the grammar
+ * is responsible for enforcing this!
+ */
+typedef struct A_Indirection
+{
+	NodeTag		type;
+	Node	   *arg;			/* the thing being selected from */
+	List	   *indirection;	/* subscripts and/or field names and/or * */
+} A_Indirection;
+
+/*
+ * A_ArrayExpr - an ARRAY[] construct
+ */
+typedef struct A_ArrayExpr
+{
+	NodeTag		type;
+	List	   *elements;		/* array element expressions */
+	int			location;		/* token location, or -1 if unknown */
+} A_ArrayExpr;
+
+/*
+ * ResTarget -
+ *	  result target (used in target list of pre-transformed parse trees)
+ *
+ * In a SELECT target list, 'name' is the column label from an
+ * 'AS ColumnLabel' clause, or NULL if there was none, and 'val' is the
+ * value expression itself.  The 'indirection' field is not used.
+ *
+ * INSERT uses ResTarget in its target-column-names list.  Here, 'name' is
+ * the name of the destination column, 'indirection' stores any subscripts
+ * attached to the destination, and 'val' is not used.
+ *
+ * In an UPDATE target list, 'name' is the name of the destination column,
+ * 'indirection' stores any subscripts attached to the destination, and
+ * 'val' is the expression to assign.
+ *
+ * See A_Indirection for more info about what can appear in 'indirection'.
+ */
+typedef struct ResTarget
+{
+	NodeTag		type;
+	char	   *name;			/* column name or NULL */
+	List	   *indirection;	/* subscripts, field names, and '*', or NIL */
+	Node	   *val;			/* the value expression to compute or assign */
+	int			location;		/* token location, or -1 if unknown */
+} ResTarget;
+
+/*
+ * MultiAssignRef - element of a row source expression for UPDATE
+ *
+ * In an UPDATE target list, when we have SET (a,b,c) = row-valued-expression,
+ * we generate separate ResTarget items for each of a,b,c.  Their "val" trees
+ * are MultiAssignRef nodes numbered 1..n, linking to a common copy of the
+ * row-valued-expression (which parse analysis will process only once, when
+ * handling the MultiAssignRef with colno=1).
+ */
+typedef struct MultiAssignRef
+{
+	NodeTag		type;
+	Node	   *source;			/* the row-valued expression */
+	int			colno;			/* column number for this target (1..n) */
+	int			ncolumns;		/* number of targets in the construct */
+} MultiAssignRef;
+
+/*
+ * SortBy - for ORDER BY clause
+ */
+typedef struct SortBy
+{
+	NodeTag		type;
+	Node	   *node;			/* expression to sort on */
+	SortByDir	sortby_dir;		/* ASC/DESC/USING/default */
+	SortByNulls sortby_nulls;	/* NULLS FIRST/LAST */
+	List	   *useOp;			/* name of op to use, if SORTBY_USING */
+	int			location;		/* operator location, or -1 if none/unknown */
+} SortBy;
+
+/*
+ * WindowDef - raw representation of WINDOW and OVER clauses
+ *
+ * For entries in a WINDOW list, "name" is the window name being defined.
+ * For OVER clauses, we use "name" for the "OVER window" syntax, or "refname"
+ * for the "OVER (window)" syntax, which is subtly different --- the latter
+ * implies overriding the window frame clause.
+ */
+typedef struct WindowDef
+{
+	NodeTag		type;
+	char	   *name;			/* window's own name */
+	char	   *refname;		/* referenced window name, if any */
+	List	   *partitionClause;	/* PARTITION BY expression list */
+	List	   *orderClause;	/* ORDER BY (list of SortBy) */
+	int			frameOptions;	/* frame_clause options, see below */
+	Node	   *startOffset;	/* expression for starting bound, if any */
+	Node	   *endOffset;		/* expression for ending bound, if any */
+	int			location;		/* parse location, or -1 if none/unknown */
+} WindowDef;
+
+/*
+ * frameOptions is an OR of these bits.  The NONDEFAULT and BETWEEN bits are
+ * used so that ruleutils.c can tell which properties were specified and
+ * which were defaulted; the correct behavioral bits must be set either way.
+ * The START_foo and END_foo options must come in pairs of adjacent bits for
+ * the convenience of gram.y, even though some of them are useless/invalid.
+ */
+#define FRAMEOPTION_NONDEFAULT					0x00001 /* any specified? */
+#define FRAMEOPTION_RANGE						0x00002 /* RANGE behavior */
+#define FRAMEOPTION_ROWS						0x00004 /* ROWS behavior */
+#define FRAMEOPTION_GROUPS						0x00008 /* GROUPS behavior */
+#define FRAMEOPTION_BETWEEN						0x00010 /* BETWEEN given? */
+#define FRAMEOPTION_START_UNBOUNDED_PRECEDING	0x00020 /* start is U. P. */
+#define FRAMEOPTION_END_UNBOUNDED_PRECEDING		0x00040 /* (disallowed) */
+#define FRAMEOPTION_START_UNBOUNDED_FOLLOWING	0x00080 /* (disallowed) */
+#define FRAMEOPTION_END_UNBOUNDED_FOLLOWING		0x00100 /* end is U. F. */
+#define FRAMEOPTION_START_CURRENT_ROW			0x00200 /* start is C. R. */
+#define FRAMEOPTION_END_CURRENT_ROW				0x00400 /* end is C. R. */
+#define FRAMEOPTION_START_OFFSET_PRECEDING		0x00800 /* start is O. P. */
+#define FRAMEOPTION_END_OFFSET_PRECEDING		0x01000 /* end is O. P. */
+#define FRAMEOPTION_START_OFFSET_FOLLOWING		0x02000 /* start is O. F. */
+#define FRAMEOPTION_END_OFFSET_FOLLOWING		0x04000 /* end is O. F. */
+#define FRAMEOPTION_EXCLUDE_CURRENT_ROW			0x08000 /* omit C.R. */
+#define FRAMEOPTION_EXCLUDE_GROUP				0x10000 /* omit C.R. & peers */
+#define FRAMEOPTION_EXCLUDE_TIES				0x20000 /* omit C.R.'s peers */
+
+#define FRAMEOPTION_START_OFFSET \
+	(FRAMEOPTION_START_OFFSET_PRECEDING | FRAMEOPTION_START_OFFSET_FOLLOWING)
+#define FRAMEOPTION_END_OFFSET \
+	(FRAMEOPTION_END_OFFSET_PRECEDING | FRAMEOPTION_END_OFFSET_FOLLOWING)
+#define FRAMEOPTION_EXCLUSION \
+	(FRAMEOPTION_EXCLUDE_CURRENT_ROW | FRAMEOPTION_EXCLUDE_GROUP | \
+	 FRAMEOPTION_EXCLUDE_TIES)
+
+#define FRAMEOPTION_DEFAULTS \
+	(FRAMEOPTION_RANGE | FRAMEOPTION_START_UNBOUNDED_PRECEDING | \
+	 FRAMEOPTION_END_CURRENT_ROW)
+
+/*
+ * RangeSubselect - subquery appearing in a FROM clause
+ */
+typedef struct RangeSubselect
+{
+	NodeTag		type;
+	bool		lateral;		/* does it have LATERAL prefix? */
+	Node	   *subquery;		/* the untransformed sub-select clause */
+	Alias	   *alias;			/* table alias & optional column aliases */
+} RangeSubselect;
+
+/*
+ * RangeFunction - function call appearing in a FROM clause
+ *
+ * functions is a List because we use this to represent the construct
+ * ROWS FROM(func1(...), func2(...), ...).  Each element of this list is a
+ * two-element sublist, the first element being the untransformed function
+ * call tree, and the second element being a possibly-empty list of ColumnDef
+ * nodes representing any columndef list attached to that function within the
+ * ROWS FROM() syntax.
+ *
+ * alias and coldeflist represent any alias and/or columndef list attached
+ * at the top level.  (We disallow coldeflist appearing both here and
+ * per-function, but that's checked in parse analysis, not by the grammar.)
+ */
+typedef struct RangeFunction
+{
+	NodeTag		type;
+	bool		lateral;		/* does it have LATERAL prefix? */
+	bool		ordinality;		/* does it have WITH ORDINALITY suffix? */
+	bool		is_rowsfrom;	/* is result of ROWS FROM() syntax? */
+	List	   *functions;		/* per-function information, see above */
+	Alias	   *alias;			/* table alias & optional column aliases */
+	List	   *coldeflist;		/* list of ColumnDef nodes to describe result
+								 * of function returning RECORD */
+} RangeFunction;
+
+/*
+ * RangeTableFunc - raw form of "table functions" such as XMLTABLE
+ */
+typedef struct RangeTableFunc
+{
+	NodeTag		type;
+	bool		lateral;		/* does it have LATERAL prefix? */
+	Node	   *docexpr;		/* document expression */
+	Node	   *rowexpr;		/* row generator expression */
+	List	   *namespaces;		/* list of namespaces as ResTarget */
+	List	   *columns;		/* list of RangeTableFuncCol */
+	Alias	   *alias;			/* table alias & optional column aliases */
+	int			location;		/* token location, or -1 if unknown */
+} RangeTableFunc;
+
+/*
+ * RangeTableFuncCol - one column in a RangeTableFunc->columns
+ *
+ * If for_ordinality is true (FOR ORDINALITY), then the column is an int4
+ * column and the rest of the fields are ignored.
+ */
+typedef struct RangeTableFuncCol
+{
+	NodeTag		type;
+	char	   *colname;		/* name of generated column */
+	TypeName   *typeName;		/* type of generated column */
+	bool		for_ordinality; /* does it have FOR ORDINALITY? */
+	bool		is_not_null;	/* does it have NOT NULL? */
+	Node	   *colexpr;		/* column filter expression */
+	Node	   *coldefexpr;		/* column default value expression */
+	int			location;		/* token location, or -1 if unknown */
+} RangeTableFuncCol;
+
+/*
+ * RangeTableSample - TABLESAMPLE appearing in a raw FROM clause
+ *
+ * This node, appearing only in raw parse trees, represents
+ *		<relation> TABLESAMPLE <method> (<params>) REPEATABLE (<num>)
+ * Currently, the <relation> can only be a RangeVar, but we might in future
+ * allow RangeSubselect and other options.  Note that the RangeTableSample
+ * is wrapped around the node representing the <relation>, rather than being
+ * a subfield of it.
+ */
+typedef struct RangeTableSample
+{
+	NodeTag		type;
+	Node	   *relation;		/* relation to be sampled */
+	List	   *method;			/* sampling method name (possibly qualified) */
+	List	   *args;			/* argument(s) for sampling method */
+	Node	   *repeatable;		/* REPEATABLE expression, or NULL if none */
+	int			location;		/* method name location, or -1 if unknown */
+} RangeTableSample;
+
+/*
+ * ColumnDef - column definition (used in various creates)
+ *
+ * If the column has a default value, we may have the value expression
+ * in either "raw" form (an untransformed parse tree) or "cooked" form
+ * (a post-parse-analysis, executable expression tree), depending on
+ * how this ColumnDef node was created (by parsing, or by inheritance
+ * from an existing relation).  We should never have both in the same node!
+ *
+ * Similarly, we may have a COLLATE specification in either raw form
+ * (represented as a CollateClause with arg==NULL) or cooked form
+ * (the collation's OID).
+ *
+ * The constraints list may contain a CONSTR_DEFAULT item in a raw
+ * parsetree produced by gram.y, but transformCreateStmt will remove
+ * the item and set raw_default instead.  CONSTR_DEFAULT items
+ * should not appear in any subsequent processing.
+ */
+typedef struct ColumnDef
+{
+	NodeTag		type;
+	char	   *colname;		/* name of column */
+	TypeName   *typeName;		/* type of column */
+	int			inhcount;		/* number of times column is inherited */
+	bool		is_local;		/* column has local (non-inherited) def'n */
+	bool		is_not_null;	/* NOT NULL constraint specified? */
+	bool		is_from_type;	/* column definition came from table type */
+	char		storage;		/* attstorage setting, or 0 for default */
+	Node	   *raw_default;	/* default value (untransformed parse tree) */
+	Node	   *cooked_default; /* default value (transformed expr tree) */
+	char		identity;		/* attidentity setting */
+	RangeVar   *identitySequence;	/* to store identity sequence name for
+									 * ALTER TABLE ... ADD COLUMN */
+	char		generated;		/* attgenerated setting */
+	CollateClause *collClause;	/* untransformed COLLATE spec, if any */
+	Oid			collOid;		/* collation OID (InvalidOid if not set) */
+	List	   *constraints;	/* other constraints on column */
+	List	   *fdwoptions;		/* per-column FDW options */
+	int			location;		/* parse location, or -1 if none/unknown */
+} ColumnDef;
+
+/*
+ * TableLikeClause - CREATE TABLE ( ... LIKE ... ) clause
+ */
+typedef struct TableLikeClause
+{
+	NodeTag		type;
+	RangeVar   *relation;
+	bits32		options;		/* OR of TableLikeOption flags */
+	Oid			relationOid;	/* If table has been looked up, its OID */
+} TableLikeClause;
+
+typedef enum TableLikeOption
+{
+	CREATE_TABLE_LIKE_COMMENTS = 1 << 0,
+	CREATE_TABLE_LIKE_CONSTRAINTS = 1 << 1,
+	CREATE_TABLE_LIKE_DEFAULTS = 1 << 2,
+	CREATE_TABLE_LIKE_GENERATED = 1 << 3,
+	CREATE_TABLE_LIKE_IDENTITY = 1 << 4,
+	CREATE_TABLE_LIKE_INDEXES = 1 << 5,
+	CREATE_TABLE_LIKE_STATISTICS = 1 << 6,
+	CREATE_TABLE_LIKE_STORAGE = 1 << 7,
+	CREATE_TABLE_LIKE_ALL = PG_INT32_MAX
+} TableLikeOption;
+
+/*
+ * IndexElem - index parameters (used in CREATE INDEX, and in ON CONFLICT)
+ *
+ * For a plain index attribute, 'name' is the name of the table column to
+ * index, and 'expr' is NULL.  For an index expression, 'name' is NULL and
+ * 'expr' is the expression tree.
+ */
+typedef struct IndexElem
+{
+	NodeTag		type;
+	char	   *name;			/* name of attribute to index, or NULL */
+	Node	   *expr;			/* expression to index, or NULL */
+	char	   *indexcolname;	/* name for index column; NULL = default */
+	List	   *collation;		/* name of collation; NIL = default */
+	List	   *opclass;		/* name of desired opclass; NIL = default */
+	List	   *opclassopts;	/* opclass-specific options, or NIL */
+	SortByDir	ordering;		/* ASC/DESC/default */
+	SortByNulls nulls_ordering; /* FIRST/LAST/default */
+} IndexElem;
+
+/*
+ * DefElem - a generic "name = value" option definition
+ *
+ * In some contexts the name can be qualified.  Also, certain SQL commands
+ * allow a SET/ADD/DROP action to be attached to option settings, so it's
+ * convenient to carry a field for that too.  (Note: currently, it is our
+ * practice that the grammar allows namespace and action only in statements
+ * where they are relevant; C code can just ignore those fields in other
+ * statements.)
+ */
+typedef enum DefElemAction
+{
+	DEFELEM_UNSPEC,				/* no action given */
+	DEFELEM_SET,
+	DEFELEM_ADD,
+	DEFELEM_DROP
+} DefElemAction;
+
+typedef struct DefElem
+{
+	NodeTag		type;
+	char	   *defnamespace;	/* NULL if unqualified name */
+	char	   *defname;
+	Node	   *arg;			/* a (Value *) or a (TypeName *) */
+	DefElemAction defaction;	/* unspecified action, or SET/ADD/DROP */
+	int			location;		/* token location, or -1 if unknown */
+} DefElem;
+
+/*
+ * LockingClause - raw representation of FOR [NO KEY] UPDATE/[KEY] SHARE
+ *		options
+ *
+ * Note: lockedRels == NIL means "all relations in query".  Otherwise it
+ * is a list of RangeVar nodes.  (We use RangeVar mainly because it carries
+ * a location field --- currently, parse analysis insists on unqualified
+ * names in LockingClause.)
+ */
+typedef struct LockingClause
+{
+	NodeTag		type;
+	List	   *lockedRels;		/* FOR [KEY] UPDATE/SHARE relations */
+	LockClauseStrength strength;
+	LockWaitPolicy waitPolicy;	/* NOWAIT and SKIP LOCKED */
+} LockingClause;
+
+/*
+ * XMLSERIALIZE (in raw parse tree only)
+ */
+typedef struct XmlSerialize
+{
+	NodeTag		type;
+	XmlOptionType xmloption;	/* DOCUMENT or CONTENT */
+	Node	   *expr;
+	TypeName   *typeName;
+	int			location;		/* token location, or -1 if unknown */
+} XmlSerialize;
+
+/* Partitioning related definitions */
+
+/*
+ * PartitionElem - parse-time representation of a single partition key
+ *
+ * expr can be either a raw expression tree or a parse-analyzed expression.
+ * We don't store these on-disk, though.
+ */
+typedef struct PartitionElem
+{
+	NodeTag		type;
+	char	   *name;			/* name of column to partition on, or NULL */
+	Node	   *expr;			/* expression to partition on, or NULL */
+	List	   *collation;		/* name of collation; NIL = default */
+	List	   *opclass;		/* name of desired opclass; NIL = default */
+	int			location;		/* token location, or -1 if unknown */
+} PartitionElem;
+
+/*
+ * PartitionSpec - parse-time representation of a partition key specification
+ *
+ * This represents the key space we will be partitioning on.
+ */
+typedef struct PartitionSpec
+{
+	NodeTag		type;
+	char	   *strategy;		/* partitioning strategy ('hash', 'list' or
+								 * 'range') */
+	List	   *partParams;		/* List of PartitionElems */
+	int			location;		/* token location, or -1 if unknown */
+} PartitionSpec;
+
+/* Internal codes for partitioning strategies */
+#define PARTITION_STRATEGY_HASH		'h'
+#define PARTITION_STRATEGY_LIST		'l'
+#define PARTITION_STRATEGY_RANGE	'r'
+
+/*
+ * PartitionBoundSpec - a partition bound specification
+ *
+ * This represents the portion of the partition key space assigned to a
+ * particular partition.  These are stored on disk in pg_class.relpartbound.
+ */
+struct PartitionBoundSpec
+{
+	NodeTag		type;
+
+	char		strategy;		/* see PARTITION_STRATEGY codes above */
+	bool		is_default;		/* is it a default partition bound? */
+
+	/* Partitioning info for HASH strategy: */
+	int			modulus;
+	int			remainder;
+
+	/* Partitioning info for LIST strategy: */
+	List	   *listdatums;		/* List of Consts (or A_Consts in raw tree) */
+
+	/* Partitioning info for RANGE strategy: */
+	List	   *lowerdatums;	/* List of PartitionRangeDatums */
+	List	   *upperdatums;	/* List of PartitionRangeDatums */
+
+	int			location;		/* token location, or -1 if unknown */
+};
+
+/*
+ * PartitionRangeDatum - one of the values in a range partition bound
+ *
+ * This can be MINVALUE, MAXVALUE or a specific bounded value.
+ */
+typedef enum PartitionRangeDatumKind
+{
+	PARTITION_RANGE_DATUM_MINVALUE = -1,	/* less than any other value */
+	PARTITION_RANGE_DATUM_VALUE = 0,	/* a specific (bounded) value */
+	PARTITION_RANGE_DATUM_MAXVALUE = 1	/* greater than any other value */
+} PartitionRangeDatumKind;
+
+typedef struct PartitionRangeDatum
+{
+	NodeTag		type;
+
+	PartitionRangeDatumKind kind;
+	Node	   *value;			/* Const (or A_Const in raw tree), if kind is
+								 * PARTITION_RANGE_DATUM_VALUE, else NULL */
+
+	int			location;		/* token location, or -1 if unknown */
+} PartitionRangeDatum;
+
+/*
+ * PartitionCmd - info for ALTER TABLE/INDEX ATTACH/DETACH PARTITION commands
+ */
+typedef struct PartitionCmd
+{
+	NodeTag		type;
+	RangeVar   *name;			/* name of partition to attach/detach */
+	PartitionBoundSpec *bound;	/* FOR VALUES, if attaching */
+} PartitionCmd;
+
+/****************************************************************************
+ *	Nodes for a Query tree
+ ****************************************************************************/
+
+/*--------------------
+ * RangeTblEntry -
+ *	  A range table is a List of RangeTblEntry nodes.
+ *
+ *	  A range table entry may represent a plain relation, a sub-select in
+ *	  FROM, or the result of a JOIN clause.  (Only explicit JOIN syntax
+ *	  produces an RTE, not the implicit join resulting from multiple FROM
+ *	  items.  This is because we only need the RTE to deal with SQL features
+ *	  like outer joins and join-output-column aliasing.)  Other special
+ *	  RTE types also exist, as indicated by RTEKind.
+ *
+ *	  Note that we consider RTE_RELATION to cover anything that has a pg_class
+ *	  entry.  relkind distinguishes the sub-cases.
+ *
+ *	  alias is an Alias node representing the AS alias-clause attached to the
+ *	  FROM expression, or NULL if no clause.
+ *
+ *	  eref is the table reference name and column reference names (either
+ *	  real or aliases).  Note that system columns (OID etc) are not included
+ *	  in the column list.
+ *	  eref->aliasname is required to be present, and should generally be used
+ *	  to identify the RTE for error messages etc.
+ *
+ *	  In RELATION RTEs, the colnames in both alias and eref are indexed by
+ *	  physical attribute number; this means there must be colname entries for
+ *	  dropped columns.  When building an RTE we insert empty strings ("") for
+ *	  dropped columns.  Note however that a stored rule may have nonempty
+ *	  colnames for columns dropped since the rule was created (and for that
+ *	  matter the colnames might be out of date due to column renamings).
+ *	  The same comments apply to FUNCTION RTEs when a function's return type
+ *	  is a named composite type.
+ *
+ *	  In JOIN RTEs, the colnames in both alias and eref are one-to-one with
+ *	  joinaliasvars entries.  A JOIN RTE will omit columns of its inputs when
+ *	  those columns are known to be dropped at parse time.  Again, however,
+ *	  a stored rule might contain entries for columns dropped since the rule
+ *	  was created.  (This is only possible for columns not actually referenced
+ *	  in the rule.)  When loading a stored rule, we replace the joinaliasvars
+ *	  items for any such columns with null pointers.  (We can't simply delete
+ *	  them from the joinaliasvars list, because that would affect the attnums
+ *	  of Vars referencing the rest of the list.)
+ *
+ *	  inh is true for relation references that should be expanded to include
+ *	  inheritance children, if the rel has any.  This *must* be false for
+ *	  RTEs other than RTE_RELATION entries.
+ *
+ *	  inFromCl marks those range variables that are listed in the FROM clause.
+ *	  It's false for RTEs that are added to a query behind the scenes, such
+ *	  as the NEW and OLD variables for a rule, or the subqueries of a UNION.
+ *	  This flag is not used anymore during parsing, since the parser now uses
+ *	  a separate "namespace" data structure to control visibility, but it is
+ *	  needed by ruleutils.c to determine whether RTEs should be shown in
+ *	  decompiled queries.
+ *
+ *	  requiredPerms and checkAsUser specify run-time access permissions
+ *	  checks to be performed at query startup.  The user must have *all*
+ *	  of the permissions that are OR'd together in requiredPerms (zero
+ *	  indicates no permissions checking).  If checkAsUser is not zero,
+ *	  then do the permissions checks using the access rights of that user,
+ *	  not the current effective user ID.  (This allows rules to act as
+ *	  setuid gateways.)  Permissions checks only apply to RELATION RTEs.
+ *
+ *	  For SELECT/INSERT/UPDATE permissions, if the user doesn't have
+ *	  table-wide permissions then it is sufficient to have the permissions
+ *	  on all columns identified in selectedCols (for SELECT) and/or
+ *	  insertedCols and/or updatedCols (INSERT with ON CONFLICT DO UPDATE may
+ *	  have all 3).  selectedCols, insertedCols and updatedCols are bitmapsets,
+ *	  which cannot have negative integer members, so we subtract
+ *	  FirstLowInvalidHeapAttributeNumber from column numbers before storing
+ *	  them in these fields.  A whole-row Var reference is represented by
+ *	  setting the bit for InvalidAttrNumber.
+ *
+ *	  updatedCols is also used in some other places, for example, to determine
+ *	  which triggers to fire and in FDWs to know which changed columns they
+ *	  need to ship off.
+ *
+ *	  Generated columns that are caused to be updated by an update to a base
+ *	  column are listed in extraUpdatedCols.  This is not considered for
+ *	  permission checking, but it is useful in those places that want to know
+ *	  the full set of columns being updated as opposed to only the ones the
+ *	  user explicitly mentioned in the query.  (There is currently no need for
+ *	  an extraInsertedCols, but it could exist.)  Note that extraUpdatedCols
+ *	  is populated during query rewrite, NOT in the parser, since generated
+ *	  columns could be added after a rule has been parsed and stored.
+ *
+ *	  securityQuals is a list of security barrier quals (boolean expressions),
+ *	  to be tested in the listed order before returning a row from the
+ *	  relation.  It is always NIL in parser output.  Entries are added by the
+ *	  rewriter to implement security-barrier views and/or row-level security.
+ *	  Note that the planner turns each boolean expression into an implicitly
+ *	  AND'ed sublist, as is its usual habit with qualification expressions.
+ *--------------------
+ */
+typedef enum RTEKind
+{
+	RTE_RELATION,				/* ordinary relation reference */
+	RTE_SUBQUERY,				/* subquery in FROM */
+	RTE_JOIN,					/* join */
+	RTE_FUNCTION,				/* function in FROM */
+	RTE_TABLEFUNC,				/* TableFunc(.., column list) */
+	RTE_VALUES,					/* VALUES (<exprlist>), (<exprlist>), ... */
+	RTE_CTE,					/* common table expr (WITH list element) */
+	RTE_NAMEDTUPLESTORE,		/* tuplestore, e.g. for AFTER triggers */
+	RTE_RESULT					/* RTE represents an empty FROM clause; such
+								 * RTEs are added by the planner, they're not
+								 * present during parsing or rewriting */
+} RTEKind;
+
+typedef struct RangeTblEntry
+{
+	NodeTag		type;
+
+	RTEKind		rtekind;		/* see above */
+
+	/*
+	 * XXX the fields applicable to only some rte kinds should be merged into
+	 * a union.  I didn't do this yet because the diffs would impact a lot of
+	 * code that is being actively worked on.  FIXME someday.
+	 */
+
+	/*
+	 * Fields valid for a plain relation RTE (else zero):
+	 *
+	 * As a special case, RTE_NAMEDTUPLESTORE can also set relid to indicate
+	 * that the tuple format of the tuplestore is the same as the referenced
+	 * relation.  This allows plans referencing AFTER trigger transition
+	 * tables to be invalidated if the underlying table is altered.
+	 *
+	 * rellockmode is really LOCKMODE, but it's declared int to avoid having
+	 * to include lock-related headers here.  It must be RowExclusiveLock if
+	 * the RTE is an INSERT/UPDATE/DELETE target, else RowShareLock if the RTE
+	 * is a SELECT FOR UPDATE/FOR SHARE target, else AccessShareLock.
+	 *
+	 * Note: in some cases, rule expansion may result in RTEs that are marked
+	 * with RowExclusiveLock even though they are not the target of the
+	 * current query; this happens if a DO ALSO rule simply scans the original
+	 * target table.  We leave such RTEs with their original lockmode so as to
+	 * avoid getting an additional, lesser lock.
+	 */
+	Oid			relid;			/* OID of the relation */
+	char		relkind;		/* relation kind (see pg_class.relkind) */
+	int			rellockmode;	/* lock level that query requires on the rel */
+	struct TableSampleClause *tablesample;	/* sampling info, or NULL */
+
+	/*
+	 * Fields valid for a subquery RTE (else NULL):
+	 */
+	Query	   *subquery;		/* the sub-query */
+	bool		security_barrier;	/* is from security_barrier view? */
+
+	/*
+	 * Fields valid for a join RTE (else NULL/zero):
+	 *
+	 * joinaliasvars is a list of (usually) Vars corresponding to the columns
+	 * of the join result.  An alias Var referencing column K of the join
+	 * result can be replaced by the K'th element of joinaliasvars --- but to
+	 * simplify the task of reverse-listing aliases correctly, we do not do
+	 * that until planning time.  In detail: an element of joinaliasvars can
+	 * be a Var of one of the join's input relations, or such a Var with an
+	 * implicit coercion to the join's output column type, or a COALESCE
+	 * expression containing the two input column Vars (possibly coerced).
+	 * Elements beyond the first joinmergedcols entries are always just Vars,
+	 * and are never referenced from elsewhere in the query (that is, join
+	 * alias Vars are generated only for merged columns).  We keep these
+	 * entries only because they're needed in expandRTE() and similar code.
+	 *
+	 * Within a Query loaded from a stored rule, it is possible for non-merged
+	 * joinaliasvars items to be null pointers, which are placeholders for
+	 * (necessarily unreferenced) columns dropped since the rule was made.
+	 * Also, once planning begins, joinaliasvars items can be almost anything,
+	 * as a result of subquery-flattening substitutions.
+	 *
+	 * joinleftcols is an integer list of physical column numbers of the left
+	 * join input rel that are included in the join; likewise joinrighttcols
+	 * for the right join input rel.  (Which rels those are can be determined
+	 * from the associated JoinExpr.)  If the join is USING/NATURAL, then the
+	 * first joinmergedcols entries in each list identify the merged columns.
+	 * The merged columns come first in the join output, then remaining
+	 * columns of the left input, then remaining columns of the right.
+	 *
+	 * Note that input columns could have been dropped after creation of a
+	 * stored rule, if they are not referenced in the query (in particular,
+	 * merged columns could not be dropped); this is not accounted for in
+	 * joinleftcols/joinrighttcols.
+	 */
+	JoinType	jointype;		/* type of join */
+	int			joinmergedcols; /* number of merged (JOIN USING) columns */
+	List	   *joinaliasvars;	/* list of alias-var expansions */
+	List	   *joinleftcols;	/* left-side input column numbers */
+	List	   *joinrightcols;	/* right-side input column numbers */
+
+	/*
+	 * Fields valid for a function RTE (else NIL/zero):
+	 *
+	 * When funcordinality is true, the eref->colnames list includes an alias
+	 * for the ordinality column.  The ordinality column is otherwise
+	 * implicit, and must be accounted for "by hand" in places such as
+	 * expandRTE().
+	 */
+	List	   *functions;		/* list of RangeTblFunction nodes */
+	bool		funcordinality; /* is this called WITH ORDINALITY? */
+
+	/*
+	 * Fields valid for a TableFunc RTE (else NULL):
+	 */
+	TableFunc  *tablefunc;
+
+	/*
+	 * Fields valid for a values RTE (else NIL):
+	 */
+	List	   *values_lists;	/* list of expression lists */
+
+	/*
+	 * Fields valid for a CTE RTE (else NULL/zero):
+	 */
+	char	   *ctename;		/* name of the WITH list item */
+	Index		ctelevelsup;	/* number of query levels up */
+	bool		self_reference; /* is this a recursive self-reference? */
+
+	/*
+	 * Fields valid for CTE, VALUES, ENR, and TableFunc RTEs (else NIL):
+	 *
+	 * We need these for CTE RTEs so that the types of self-referential
+	 * columns are well-defined.  For VALUES RTEs, storing these explicitly
+	 * saves having to re-determine the info by scanning the values_lists. For
+	 * ENRs, we store the types explicitly here (we could get the information
+	 * from the catalogs if 'relid' was supplied, but we'd still need these
+	 * for TupleDesc-based ENRs, so we might as well always store the type
+	 * info here).  For TableFuncs, these fields are redundant with data in
+	 * the TableFunc node, but keeping them here allows some code sharing with
+	 * the other cases.
+	 *
+	 * For ENRs only, we have to consider the possibility of dropped columns.
+	 * A dropped column is included in these lists, but it will have zeroes in
+	 * all three lists (as well as an empty-string entry in eref).  Testing
+	 * for zero coltype is the standard way to detect a dropped column.
+	 */
+	List	   *coltypes;		/* OID list of column type OIDs */
+	List	   *coltypmods;		/* integer list of column typmods */
+	List	   *colcollations;	/* OID list of column collation OIDs */
+
+	/*
+	 * Fields valid for ENR RTEs (else NULL/zero):
+	 */
+	char	   *enrname;		/* name of ephemeral named relation */
+	double		enrtuples;		/* estimated or actual from caller */
+
+	/*
+	 * Fields valid in all RTEs:
+	 */
+	Alias	   *alias;			/* user-written alias clause, if any */
+	Alias	   *eref;			/* expanded reference names */
+	bool		lateral;		/* subquery, function, or values is LATERAL? */
+	bool		inh;			/* inheritance requested? */
+	bool		inFromCl;		/* present in FROM clause? */
+	AclMode		requiredPerms;	/* bitmask of required access permissions */
+	Oid			checkAsUser;	/* if valid, check access as this role */
+	Bitmapset  *selectedCols;	/* columns needing SELECT permission */
+	Bitmapset  *insertedCols;	/* columns needing INSERT permission */
+	Bitmapset  *updatedCols;	/* columns needing UPDATE permission */
+	Bitmapset  *extraUpdatedCols;	/* generated columns being updated */
+	List	   *securityQuals;	/* security barrier quals to apply, if any */
+} RangeTblEntry;
+
+/*
+ * RangeTblFunction -
+ *	  RangeTblEntry subsidiary data for one function in a FUNCTION RTE.
+ *
+ * If the function had a column definition list (required for an
+ * otherwise-unspecified RECORD result), funccolnames lists the names given
+ * in the definition list, funccoltypes lists their declared column types,
+ * funccoltypmods lists their typmods, funccolcollations their collations.
+ * Otherwise, those fields are NIL.
+ *
+ * Notice we don't attempt to store info about the results of functions
+ * returning named composite types, because those can change from time to
+ * time.  We do however remember how many columns we thought the type had
+ * (including dropped columns!), so that we can successfully ignore any
+ * columns added after the query was parsed.
+ */
+typedef struct RangeTblFunction
+{
+	NodeTag		type;
+
+	Node	   *funcexpr;		/* expression tree for func call */
+	int			funccolcount;	/* number of columns it contributes to RTE */
+	/* These fields record the contents of a column definition list, if any: */
+	List	   *funccolnames;	/* column names (list of String) */
+	List	   *funccoltypes;	/* OID list of column type OIDs */
+	List	   *funccoltypmods; /* integer list of column typmods */
+	List	   *funccolcollations;	/* OID list of column collation OIDs */
+	/* This is set during planning for use by the executor: */
+	Bitmapset  *funcparams;		/* PARAM_EXEC Param IDs affecting this func */
+} RangeTblFunction;
+
+/*
+ * TableSampleClause - TABLESAMPLE appearing in a transformed FROM clause
+ *
+ * Unlike RangeTableSample, this is a subnode of the relevant RangeTblEntry.
+ */
+typedef struct TableSampleClause
+{
+	NodeTag		type;
+	Oid			tsmhandler;		/* OID of the tablesample handler function */
+	List	   *args;			/* tablesample argument expression(s) */
+	Expr	   *repeatable;		/* REPEATABLE expression, or NULL if none */
+} TableSampleClause;
+
+/*
+ * WithCheckOption -
+ *		representation of WITH CHECK OPTION checks to be applied to new tuples
+ *		when inserting/updating an auto-updatable view, or RLS WITH CHECK
+ *		policies to be applied when inserting/updating a relation with RLS.
+ */
+typedef enum WCOKind
+{
+	WCO_VIEW_CHECK,				/* WCO on an auto-updatable view */
+	WCO_RLS_INSERT_CHECK,		/* RLS INSERT WITH CHECK policy */
+	WCO_RLS_UPDATE_CHECK,		/* RLS UPDATE WITH CHECK policy */
+	WCO_RLS_CONFLICT_CHECK		/* RLS ON CONFLICT DO UPDATE USING policy */
+} WCOKind;
+
+typedef struct WithCheckOption
+{
+	NodeTag		type;
+	WCOKind		kind;			/* kind of WCO */
+	char	   *relname;		/* name of relation that specified the WCO */
+	char	   *polname;		/* name of RLS policy being checked */
+	Node	   *qual;			/* constraint qual to check */
+	bool		cascaded;		/* true for a cascaded WCO on a view */
+} WithCheckOption;
+
+/*
+ * SortGroupClause -
+ *		representation of ORDER BY, GROUP BY, PARTITION BY,
+ *		DISTINCT, DISTINCT ON items
+ *
+ * You might think that ORDER BY is only interested in defining ordering,
+ * and GROUP/DISTINCT are only interested in defining equality.  However,
+ * one way to implement grouping is to sort and then apply a "uniq"-like
+ * filter.  So it's also interesting to keep track of possible sort operators
+ * for GROUP/DISTINCT, and in particular to try to sort for the grouping
+ * in a way that will also yield a requested ORDER BY ordering.  So we need
+ * to be able to compare ORDER BY and GROUP/DISTINCT lists, which motivates
+ * the decision to give them the same representation.
+ *
+ * tleSortGroupRef must match ressortgroupref of exactly one entry of the
+ *		query's targetlist; that is the expression to be sorted or grouped by.
+ * eqop is the OID of the equality operator.
+ * sortop is the OID of the ordering operator (a "<" or ">" operator),
+ *		or InvalidOid if not available.
+ * nulls_first means about what you'd expect.  If sortop is InvalidOid
+ *		then nulls_first is meaningless and should be set to false.
+ * hashable is true if eqop is hashable (note this condition also depends
+ *		on the datatype of the input expression).
+ *
+ * In an ORDER BY item, all fields must be valid.  (The eqop isn't essential
+ * here, but it's cheap to get it along with the sortop, and requiring it
+ * to be valid eases comparisons to grouping items.)  Note that this isn't
+ * actually enough information to determine an ordering: if the sortop is
+ * collation-sensitive, a collation OID is needed too.  We don't store the
+ * collation in SortGroupClause because it's not available at the time the
+ * parser builds the SortGroupClause; instead, consult the exposed collation
+ * of the referenced targetlist expression to find out what it is.
+ *
+ * In a grouping item, eqop must be valid.  If the eqop is a btree equality
+ * operator, then sortop should be set to a compatible ordering operator.
+ * We prefer to set eqop/sortop/nulls_first to match any ORDER BY item that
+ * the query presents for the same tlist item.  If there is none, we just
+ * use the default ordering op for the datatype.
+ *
+ * If the tlist item's type has a hash opclass but no btree opclass, then
+ * we will set eqop to the hash equality operator, sortop to InvalidOid,
+ * and nulls_first to false.  A grouping item of this kind can only be
+ * implemented by hashing, and of course it'll never match an ORDER BY item.
+ *
+ * The hashable flag is provided since we generally have the requisite
+ * information readily available when the SortGroupClause is constructed,
+ * and it's relatively expensive to get it again later.  Note there is no
+ * need for a "sortable" flag since OidIsValid(sortop) serves the purpose.
+ *
+ * A query might have both ORDER BY and DISTINCT (or DISTINCT ON) clauses.
+ * In SELECT DISTINCT, the distinctClause list is as long or longer than the
+ * sortClause list, while in SELECT DISTINCT ON it's typically shorter.
+ * The two lists must match up to the end of the shorter one --- the parser
+ * rearranges the distinctClause if necessary to make this true.  (This
+ * restriction ensures that only one sort step is needed to both satisfy the
+ * ORDER BY and set up for the Unique step.  This is semantically necessary
+ * for DISTINCT ON, and presents no real drawback for DISTINCT.)
+ */
+typedef struct SortGroupClause
+{
+	NodeTag		type;
+	Index		tleSortGroupRef;	/* reference into targetlist */
+	Oid			eqop;			/* the equality operator ('=' op) */
+	Oid			sortop;			/* the ordering operator ('<' op), or 0 */
+	bool		nulls_first;	/* do NULLs come before normal values? */
+	bool		hashable;		/* can eqop be implemented by hashing? */
+} SortGroupClause;
+
+/*
+ * GroupingSet -
+ *		representation of CUBE, ROLLUP and GROUPING SETS clauses
+ *
+ * In a Query with grouping sets, the groupClause contains a flat list of
+ * SortGroupClause nodes for each distinct expression used.  The actual
+ * structure of the GROUP BY clause is given by the groupingSets tree.
+ *
+ * In the raw parser output, GroupingSet nodes (of all types except SIMPLE
+ * which is not used) are potentially mixed in with the expressions in the
+ * groupClause of the SelectStmt.  (An expression can't contain a GroupingSet,
+ * but a list may mix GroupingSet and expression nodes.)  At this stage, the
+ * content of each node is a list of expressions, some of which may be RowExprs
+ * which represent sublists rather than actual row constructors, and nested
+ * GroupingSet nodes where legal in the grammar.  The structure directly
+ * reflects the query syntax.
+ *
+ * In parse analysis, the transformed expressions are used to build the tlist
+ * and groupClause list (of SortGroupClause nodes), and the groupingSets tree
+ * is eventually reduced to a fixed format:
+ *
+ * EMPTY nodes represent (), and obviously have no content
+ *
+ * SIMPLE nodes represent a list of one or more expressions to be treated as an
+ * atom by the enclosing structure; the content is an integer list of
+ * ressortgroupref values (see SortGroupClause)
+ *
+ * CUBE and ROLLUP nodes contain a list of one or more SIMPLE nodes.
+ *
+ * SETS nodes contain a list of EMPTY, SIMPLE, CUBE or ROLLUP nodes, but after
+ * parse analysis they cannot contain more SETS nodes; enough of the syntactic
+ * transforms of the spec have been applied that we no longer have arbitrarily
+ * deep nesting (though we still preserve the use of cube/rollup).
+ *
+ * Note that if the groupingSets tree contains no SIMPLE nodes (only EMPTY
+ * nodes at the leaves), then the groupClause will be empty, but this is still
+ * an aggregation query (similar to using aggs or HAVING without GROUP BY).
+ *
+ * As an example, the following clause:
+ *
+ * GROUP BY GROUPING SETS ((a,b), CUBE(c,(d,e)))
+ *
+ * looks like this after raw parsing:
+ *
+ * SETS( RowExpr(a,b) , CUBE( c, RowExpr(d,e) ) )
+ *
+ * and parse analysis converts it to:
+ *
+ * SETS( SIMPLE(1,2), CUBE( SIMPLE(3), SIMPLE(4,5) ) )
+ */
+typedef enum
+{
+	GROUPING_SET_EMPTY,
+	GROUPING_SET_SIMPLE,
+	GROUPING_SET_ROLLUP,
+	GROUPING_SET_CUBE,
+	GROUPING_SET_SETS
+} GroupingSetKind;
+
+typedef struct GroupingSet
+{
+	NodeTag		type;
+	GroupingSetKind kind;
+	List	   *content;
+	int			location;
+} GroupingSet;
+
+/*
+ * WindowClause -
+ *		transformed representation of WINDOW and OVER clauses
+ *
+ * A parsed Query's windowClause list contains these structs.  "name" is set
+ * if the clause originally came from WINDOW, and is NULL if it originally
+ * was an OVER clause (but note that we collapse out duplicate OVERs).
+ * partitionClause and orderClause are lists of SortGroupClause structs.
+ * If we have RANGE with offset PRECEDING/FOLLOWING, the semantics of that are
+ * specified by startInRangeFunc/inRangeColl/inRangeAsc/inRangeNullsFirst
+ * for the start offset, or endInRangeFunc/inRange* for the end offset.
+ * winref is an ID number referenced by WindowFunc nodes; it must be unique
+ * among the members of a Query's windowClause list.
+ * When refname isn't null, the partitionClause is always copied from there;
+ * the orderClause might or might not be copied (see copiedOrder); the framing
+ * options are never copied, per spec.
+ */
+typedef struct WindowClause
+{
+	NodeTag		type;
+	char	   *name;			/* window name (NULL in an OVER clause) */
+	char	   *refname;		/* referenced window name, if any */
+	List	   *partitionClause;	/* PARTITION BY list */
+	List	   *orderClause;	/* ORDER BY list */
+	int			frameOptions;	/* frame_clause options, see WindowDef */
+	Node	   *startOffset;	/* expression for starting bound, if any */
+	Node	   *endOffset;		/* expression for ending bound, if any */
+	Oid			startInRangeFunc;	/* in_range function for startOffset */
+	Oid			endInRangeFunc; /* in_range function for endOffset */
+	Oid			inRangeColl;	/* collation for in_range tests */
+	bool		inRangeAsc;		/* use ASC sort order for in_range tests? */
+	bool		inRangeNullsFirst;	/* nulls sort first for in_range tests? */
+	Index		winref;			/* ID referenced by window functions */
+	bool		copiedOrder;	/* did we copy orderClause from refname? */
+} WindowClause;
+
+/*
+ * RowMarkClause -
+ *	   parser output representation of FOR [KEY] UPDATE/SHARE clauses
+ *
+ * Query.rowMarks contains a separate RowMarkClause node for each relation
+ * identified as a FOR [KEY] UPDATE/SHARE target.  If one of these clauses
+ * is applied to a subquery, we generate RowMarkClauses for all normal and
+ * subquery rels in the subquery, but they are marked pushedDown = true to
+ * distinguish them from clauses that were explicitly written at this query
+ * level.  Also, Query.hasForUpdate tells whether there were explicit FOR
+ * UPDATE/SHARE/KEY SHARE clauses in the current query level.
+ */
+typedef struct RowMarkClause
+{
+	NodeTag		type;
+	Index		rti;			/* range table index of target relation */
+	LockClauseStrength strength;
+	LockWaitPolicy waitPolicy;	/* NOWAIT and SKIP LOCKED */
+	bool		pushedDown;		/* pushed down from higher query level? */
+} RowMarkClause;
+
+/*
+ * WithClause -
+ *	   representation of WITH clause
+ *
+ * Note: WithClause does not propagate into the Query representation;
+ * but CommonTableExpr does.
+ */
+typedef struct WithClause
+{
+	NodeTag		type;
+	List	   *ctes;			/* list of CommonTableExprs */
+	bool		recursive;		/* true = WITH RECURSIVE */
+	int			location;		/* token location, or -1 if unknown */
+} WithClause;
+
+/*
+ * InferClause -
+ *		ON CONFLICT unique index inference clause
+ *
+ * Note: InferClause does not propagate into the Query representation.
+ */
+typedef struct InferClause
+{
+	NodeTag		type;
+	List	   *indexElems;		/* IndexElems to infer unique index */
+	Node	   *whereClause;	/* qualification (partial-index predicate) */
+	char	   *conname;		/* Constraint name, or NULL if unnamed */
+	int			location;		/* token location, or -1 if unknown */
+} InferClause;
+
+/*
+ * OnConflictClause -
+ *		representation of ON CONFLICT clause
+ *
+ * Note: OnConflictClause does not propagate into the Query representation.
+ */
+typedef struct OnConflictClause
+{
+	NodeTag		type;
+	OnConflictAction action;	/* DO NOTHING or UPDATE? */
+	InferClause *infer;			/* Optional index inference clause */
+	List	   *targetList;		/* the target list (of ResTarget) */
+	Node	   *whereClause;	/* qualifications */
+	int			location;		/* token location, or -1 if unknown */
+} OnConflictClause;
+
+/*
+ * CommonTableExpr -
+ *	   representation of WITH list element
+ *
+ * We don't currently support the SEARCH or CYCLE clause.
+ */
+typedef enum CTEMaterialize
+{
+	CTEMaterializeDefault,		/* no option specified */
+	CTEMaterializeAlways,		/* MATERIALIZED */
+	CTEMaterializeNever			/* NOT MATERIALIZED */
+} CTEMaterialize;
+
+typedef struct CommonTableExpr
+{
+	NodeTag		type;
+	char	   *ctename;		/* query name (never qualified) */
+	List	   *aliascolnames;	/* optional list of column names */
+	CTEMaterialize ctematerialized; /* is this an optimization fence? */
+	/* SelectStmt/InsertStmt/etc before parse analysis, Query afterwards: */
+	Node	   *ctequery;		/* the CTE's subquery */
+	int			location;		/* token location, or -1 if unknown */
+	/* These fields are set during parse analysis: */
+	bool		cterecursive;	/* is this CTE actually recursive? */
+	int			cterefcount;	/* number of RTEs referencing this CTE
+								 * (excluding internal self-references) */
+	List	   *ctecolnames;	/* list of output column names */
+	List	   *ctecoltypes;	/* OID list of output column type OIDs */
+	List	   *ctecoltypmods;	/* integer list of output column typmods */
+	List	   *ctecolcollations;	/* OID list of column collation OIDs */
+} CommonTableExpr;
+
+/* Convenience macro to get the output tlist of a CTE's query */
+#define GetCTETargetList(cte) \
+	(AssertMacro(IsA((cte)->ctequery, Query)), \
+	 ((Query *) (cte)->ctequery)->commandType == CMD_SELECT ? \
+	 ((Query *) (cte)->ctequery)->targetList : \
+	 ((Query *) (cte)->ctequery)->returningList)
+
+/*
+ * TriggerTransition -
+ *	   representation of transition row or table naming clause
+ *
+ * Only transition tables are initially supported in the syntax, and only for
+ * AFTER triggers, but other permutations are accepted by the parser so we can
+ * give a meaningful message from C code.
+ */
+typedef struct TriggerTransition
+{
+	NodeTag		type;
+	char	   *name;
+	bool		isNew;
+	bool		isTable;
+} TriggerTransition;
+
+/*****************************************************************************
+ *		Raw Grammar Output Statements
+ *****************************************************************************/
+
+/*
+ *		RawStmt --- container for any one statement's raw parse tree
+ *
+ * Parse analysis converts a raw parse tree headed by a RawStmt node into
+ * an analyzed statement headed by a Query node.  For optimizable statements,
+ * the conversion is complex.  For utility statements, the parser usually just
+ * transfers the raw parse tree (sans RawStmt) into the utilityStmt field of
+ * the Query node, and all the useful work happens at execution time.
+ *
+ * stmt_location/stmt_len identify the portion of the source text string
+ * containing this raw statement (useful for multi-statement strings).
+ */
+typedef struct RawStmt
+{
+	NodeTag		type;
+	Node	   *stmt;			/* raw parse tree */
+	int			stmt_location;	/* start location, or -1 if unknown */
+	int			stmt_len;		/* length in bytes; 0 means "rest of string" */
+} RawStmt;
+
+/*****************************************************************************
+ *		Optimizable Statements
+ *****************************************************************************/
+
+/* ----------------------
+ *		Insert Statement
+ *
+ * The source expression is represented by SelectStmt for both the
+ * SELECT and VALUES cases.  If selectStmt is NULL, then the query
+ * is INSERT ... DEFAULT VALUES.
+ * ----------------------
+ */
+typedef struct InsertStmt
+{
+	NodeTag		type;
+	RangeVar   *relation;		/* relation to insert into */
+	List	   *cols;			/* optional: names of the target columns */
+	Node	   *selectStmt;		/* the source SELECT/VALUES, or NULL */
+	OnConflictClause *onConflictClause; /* ON CONFLICT clause */
+	List	   *returningList;	/* list of expressions to return */
+	WithClause *withClause;		/* WITH clause */
+	OverridingKind override;	/* OVERRIDING clause */
+} InsertStmt;
+
+/* ----------------------
+ *		Delete Statement
+ * ----------------------
+ */
+typedef struct DeleteStmt
+{
+	NodeTag		type;
+	RangeVar   *relation;		/* relation to delete from */
+	List	   *usingClause;	/* optional using clause for more tables */
+	Node	   *whereClause;	/* qualifications */
+	List	   *returningList;	/* list of expressions to return */
+	WithClause *withClause;		/* WITH clause */
+} DeleteStmt;
+
+/* ----------------------
+ *		Update Statement
+ * ----------------------
+ */
+typedef struct UpdateStmt
+{
+	NodeTag		type;
+	RangeVar   *relation;		/* relation to update */
+	List	   *targetList;		/* the target list (of ResTarget) */
+	Node	   *whereClause;	/* qualifications */
+	List	   *fromClause;		/* optional from clause for more tables */
+	List	   *returningList;	/* list of expressions to return */
+	WithClause *withClause;		/* WITH clause */
+} UpdateStmt;
+
+/* ----------------------
+ *		Select Statement
+ *
+ * A "simple" SELECT is represented in the output of gram.y by a single
+ * SelectStmt node; so is a VALUES construct.  A query containing set
+ * operators (UNION, INTERSECT, EXCEPT) is represented by a tree of SelectStmt
+ * nodes, in which the leaf nodes are component SELECTs and the internal nodes
+ * represent UNION, INTERSECT, or EXCEPT operators.  Using the same node
+ * type for both leaf and internal nodes allows gram.y to stick ORDER BY,
+ * LIMIT, etc, clause values into a SELECT statement without worrying
+ * whether it is a simple or compound SELECT.
+ * ----------------------
+ */
+typedef enum SetOperation
+{
+	SETOP_NONE = 0,
+	SETOP_UNION,
+	SETOP_INTERSECT,
+	SETOP_EXCEPT
+} SetOperation;
+
+typedef struct SelectStmt
+{
+	NodeTag		type;
+
+	/*
+	 * These fields are used only in "leaf" SelectStmts.
+	 */
+	List	   *distinctClause; /* NULL, list of DISTINCT ON exprs, or
+								 * lcons(NIL,NIL) for all (SELECT DISTINCT) */
+	IntoClause *intoClause;		/* target for SELECT INTO */
+	List	   *targetList;		/* the target list (of ResTarget) */
+	List	   *fromClause;		/* the FROM clause */
+	Node	   *whereClause;	/* WHERE qualification */
+	List	   *groupClause;	/* GROUP BY clauses */
+	Node	   *havingClause;	/* HAVING conditional-expression */
+	List	   *windowClause;	/* WINDOW window_name AS (...), ... */
+
+	/*
+	 * In a "leaf" node representing a VALUES list, the above fields are all
+	 * null, and instead this field is set.  Note that the elements of the
+	 * sublists are just expressions, without ResTarget decoration. Also note
+	 * that a list element can be DEFAULT (represented as a SetToDefault
+	 * node), regardless of the context of the VALUES list. It's up to parse
+	 * analysis to reject that where not valid.
+	 */
+	List	   *valuesLists;	/* untransformed list of expression lists */
+
+	/*
+	 * These fields are used in both "leaf" SelectStmts and upper-level
+	 * SelectStmts.
+	 */
+	List	   *sortClause;		/* sort clause (a list of SortBy's) */
+	Node	   *limitOffset;	/* # of result tuples to skip */
+	Node	   *limitCount;		/* # of result tuples to return */
+	LimitOption limitOption;	/* limit type */
+	List	   *lockingClause;	/* FOR UPDATE (list of LockingClause's) */
+	WithClause *withClause;		/* WITH clause */
+
+	/*
+	 * These fields are used only in upper-level SelectStmts.
+	 */
+	SetOperation op;			/* type of set op */
+	bool		all;			/* ALL specified? */
+	struct SelectStmt *larg;	/* left child */
+	struct SelectStmt *rarg;	/* right child */
+	/* Eventually add fields for CORRESPONDING spec here */
+} SelectStmt;
+
+
+/* ----------------------
+ *		Set Operation node for post-analysis query trees
+ *
+ * After parse analysis, a SELECT with set operations is represented by a
+ * top-level Query node containing the leaf SELECTs as subqueries in its
+ * range table.  Its setOperations field shows the tree of set operations,
+ * with leaf SelectStmt nodes replaced by RangeTblRef nodes, and internal
+ * nodes replaced by SetOperationStmt nodes.  Information about the output
+ * column types is added, too.  (Note that the child nodes do not necessarily
+ * produce these types directly, but we've checked that their output types
+ * can be coerced to the output column type.)  Also, if it's not UNION ALL,
+ * information about the types' sort/group semantics is provided in the form
+ * of a SortGroupClause list (same representation as, eg, DISTINCT).
+ * The resolved common column collations are provided too; but note that if
+ * it's not UNION ALL, it's okay for a column to not have a common collation,
+ * so a member of the colCollations list could be InvalidOid even though the
+ * column has a collatable type.
+ * ----------------------
+ */
+typedef struct SetOperationStmt
+{
+	NodeTag		type;
+	SetOperation op;			/* type of set op */
+	bool		all;			/* ALL specified? */
+	Node	   *larg;			/* left child */
+	Node	   *rarg;			/* right child */
+	/* Eventually add fields for CORRESPONDING spec here */
+
+	/* Fields derived during parse analysis: */
+	List	   *colTypes;		/* OID list of output column type OIDs */
+	List	   *colTypmods;		/* integer list of output column typmods */
+	List	   *colCollations;	/* OID list of output column collation OIDs */
+	List	   *groupClauses;	/* a list of SortGroupClause's */
+	/* groupClauses is NIL if UNION ALL, but must be set otherwise */
+} SetOperationStmt;
+
+
+/*****************************************************************************
+ *		Other Statements (no optimizations required)
+ *
+ *		These are not touched by parser/analyze.c except to put them into
+ *		the utilityStmt field of a Query.  This is eventually passed to
+ *		ProcessUtility (by-passing rewriting and planning).  Some of the
+ *		statements do need attention from parse analysis, and this is
+ *		done by routines in parser/parse_utilcmd.c after ProcessUtility
+ *		receives the command for execution.
+ *		DECLARE CURSOR, EXPLAIN, and CREATE TABLE AS are special cases:
+ *		they contain optimizable statements, which get processed normally
+ *		by parser/analyze.c.
+ *****************************************************************************/
+
+/*
+ * When a command can act on several kinds of objects with only one
+ * parse structure required, use these constants to designate the
+ * object type.  Note that commands typically don't support all the types.
+ */
+
+typedef enum ObjectType
+{
+	OBJECT_ACCESS_METHOD,
+	OBJECT_AGGREGATE,
+	OBJECT_AMOP,
+	OBJECT_AMPROC,
+	OBJECT_ATTRIBUTE,			/* type's attribute, when distinct from column */
+	OBJECT_CAST,
+	OBJECT_COLUMN,
+	OBJECT_COLLATION,
+	OBJECT_CONVERSION,
+	OBJECT_DATABASE,
+	OBJECT_DEFAULT,
+	OBJECT_DEFACL,
+	OBJECT_DOMAIN,
+	OBJECT_DOMCONSTRAINT,
+	OBJECT_EVENT_TRIGGER,
+	OBJECT_EXTENSION,
+	OBJECT_FDW,
+	OBJECT_FOREIGN_SERVER,
+	OBJECT_FOREIGN_TABLE,
+	OBJECT_FUNCTION,
+	OBJECT_INDEX,
+	OBJECT_LANGUAGE,
+	OBJECT_LARGEOBJECT,
+	OBJECT_MATVIEW,
+	OBJECT_OPCLASS,
+	OBJECT_OPERATOR,
+	OBJECT_OPFAMILY,
+	OBJECT_POLICY,
+	OBJECT_PROCEDURE,
+	OBJECT_PUBLICATION,
+	OBJECT_PUBLICATION_REL,
+	OBJECT_ROLE,
+	OBJECT_ROUTINE,
+	OBJECT_RULE,
+	OBJECT_SCHEMA,
+	OBJECT_SEQUENCE,
+	OBJECT_SUBSCRIPTION,
+	OBJECT_STATISTIC_EXT,
+	OBJECT_TABCONSTRAINT,
+	OBJECT_TABLE,
+	OBJECT_TABLESPACE,
+	OBJECT_TRANSFORM,
+	OBJECT_TRIGGER,
+	OBJECT_TSCONFIGURATION,
+	OBJECT_TSDICTIONARY,
+	OBJECT_TSPARSER,
+	OBJECT_TSTEMPLATE,
+	OBJECT_TYPE,
+	OBJECT_USER_MAPPING,
+	OBJECT_VIEW
+} ObjectType;
+
+/* ----------------------
+ *		Create Schema Statement
+ *
+ * NOTE: the schemaElts list contains raw parsetrees for component statements
+ * of the schema, such as CREATE TABLE, GRANT, etc.  These are analyzed and
+ * executed after the schema itself is created.
+ * ----------------------
+ */
+typedef struct CreateSchemaStmt
+{
+	NodeTag		type;
+	char	   *schemaname;		/* the name of the schema to create */
+	RoleSpec   *authrole;		/* the owner of the created schema */
+	List	   *schemaElts;		/* schema components (list of parsenodes) */
+	bool		if_not_exists;	/* just do nothing if schema already exists? */
+} CreateSchemaStmt;
+
+typedef enum DropBehavior
+{
+	DROP_RESTRICT,				/* drop fails if any dependent objects */
+	DROP_CASCADE				/* remove dependent objects too */
+} DropBehavior;
+
+/* ----------------------
+ *	Alter Table
+ * ----------------------
+ */
+typedef struct AlterTableStmt
+{
+	NodeTag		type;
+	RangeVar   *relation;		/* table to work on */
+	List	   *cmds;			/* list of subcommands */
+	ObjectType	relkind;		/* type of object */
+	bool		missing_ok;		/* skip error if table missing */
+} AlterTableStmt;
+
+typedef enum AlterTableType
+{
+	AT_AddColumn,				/* add column */
+	AT_AddColumnRecurse,		/* internal to commands/tablecmds.c */
+	AT_AddColumnToView,			/* implicitly via CREATE OR REPLACE VIEW */
+	AT_ColumnDefault,			/* alter column default */
+	AT_CookedColumnDefault,		/* add a pre-cooked column default */
+	AT_DropNotNull,				/* alter column drop not null */
+	AT_SetNotNull,				/* alter column set not null */
+	AT_DropExpression,			/* alter column drop expression */
+	AT_CheckNotNull,			/* check column is already marked not null */
+	AT_SetStatistics,			/* alter column set statistics */
+	AT_SetOptions,				/* alter column set ( options ) */
+	AT_ResetOptions,			/* alter column reset ( options ) */
+	AT_SetStorage,				/* alter column set storage */
+	AT_DropColumn,				/* drop column */
+	AT_DropColumnRecurse,		/* internal to commands/tablecmds.c */
+	AT_AddIndex,				/* add index */
+	AT_ReAddIndex,				/* internal to commands/tablecmds.c */
+	AT_AddConstraint,			/* add constraint */
+	AT_AddConstraintRecurse,	/* internal to commands/tablecmds.c */
+	AT_ReAddConstraint,			/* internal to commands/tablecmds.c */
+	AT_ReAddDomainConstraint,	/* internal to commands/tablecmds.c */
+	AT_AlterConstraint,			/* alter constraint */
+	AT_ValidateConstraint,		/* validate constraint */
+	AT_ValidateConstraintRecurse,	/* internal to commands/tablecmds.c */
+	AT_AddIndexConstraint,		/* add constraint using existing index */
+	AT_DropConstraint,			/* drop constraint */
+	AT_DropConstraintRecurse,	/* internal to commands/tablecmds.c */
+	AT_ReAddComment,			/* internal to commands/tablecmds.c */
+	AT_AlterColumnType,			/* alter column type */
+	AT_AlterColumnGenericOptions,	/* alter column OPTIONS (...) */
+	AT_ChangeOwner,				/* change owner */
+	AT_ClusterOn,				/* CLUSTER ON */
+	AT_DropCluster,				/* SET WITHOUT CLUSTER */
+	AT_SetLogged,				/* SET LOGGED */
+	AT_SetUnLogged,				/* SET UNLOGGED */
+	AT_DropOids,				/* SET WITHOUT OIDS */
+	AT_SetTableSpace,			/* SET TABLESPACE */
+	AT_SetRelOptions,			/* SET (...) -- AM specific parameters */
+	AT_ResetRelOptions,			/* RESET (...) -- AM specific parameters */
+	AT_ReplaceRelOptions,		/* replace reloption list in its entirety */
+	AT_EnableTrig,				/* ENABLE TRIGGER name */
+	AT_EnableAlwaysTrig,		/* ENABLE ALWAYS TRIGGER name */
+	AT_EnableReplicaTrig,		/* ENABLE REPLICA TRIGGER name */
+	AT_DisableTrig,				/* DISABLE TRIGGER name */
+	AT_EnableTrigAll,			/* ENABLE TRIGGER ALL */
+	AT_DisableTrigAll,			/* DISABLE TRIGGER ALL */
+	AT_EnableTrigUser,			/* ENABLE TRIGGER USER */
+	AT_DisableTrigUser,			/* DISABLE TRIGGER USER */
+	AT_EnableRule,				/* ENABLE RULE name */
+	AT_EnableAlwaysRule,		/* ENABLE ALWAYS RULE name */
+	AT_EnableReplicaRule,		/* ENABLE REPLICA RULE name */
+	AT_DisableRule,				/* DISABLE RULE name */
+	AT_AddInherit,				/* INHERIT parent */
+	AT_DropInherit,				/* NO INHERIT parent */
+	AT_AddOf,					/* OF <type_name> */
+	AT_DropOf,					/* NOT OF */
+	AT_ReplicaIdentity,			/* REPLICA IDENTITY */
+	AT_EnableRowSecurity,		/* ENABLE ROW SECURITY */
+	AT_DisableRowSecurity,		/* DISABLE ROW SECURITY */
+	AT_ForceRowSecurity,		/* FORCE ROW SECURITY */
+	AT_NoForceRowSecurity,		/* NO FORCE ROW SECURITY */
+	AT_GenericOptions,			/* OPTIONS (...) */
+	AT_AttachPartition,			/* ATTACH PARTITION */
+	AT_DetachPartition,			/* DETACH PARTITION */
+	AT_AddIdentity,				/* ADD IDENTITY */
+	AT_SetIdentity,				/* SET identity column options */
+	AT_DropIdentity				/* DROP IDENTITY */
+} AlterTableType;
+
+typedef struct ReplicaIdentityStmt
+{
+	NodeTag		type;
+	char		identity_type;
+	char	   *name;
+} ReplicaIdentityStmt;
+
+typedef struct AlterTableCmd	/* one subcommand of an ALTER TABLE */
+{
+	NodeTag		type;
+	AlterTableType subtype;		/* Type of table alteration to apply */
+	char	   *name;			/* column, constraint, or trigger to act on,
+								 * or tablespace */
+	int16		num;			/* attribute number for columns referenced by
+								 * number */
+	RoleSpec   *newowner;
+	Node	   *def;			/* definition of new column, index,
+								 * constraint, or parent table */
+	DropBehavior behavior;		/* RESTRICT or CASCADE for DROP cases */
+	bool		missing_ok;		/* skip error if missing? */
+} AlterTableCmd;
+
+
+/* ----------------------
+ * Alter Collation
+ * ----------------------
+ */
+typedef struct AlterCollationStmt
+{
+	NodeTag		type;
+	List	   *collname;
+} AlterCollationStmt;
+
+
+/* ----------------------
+ *	Alter Domain
+ *
+ * The fields are used in different ways by the different variants of
+ * this command.
+ * ----------------------
+ */
+typedef struct AlterDomainStmt
+{
+	NodeTag		type;
+	char		subtype;		/*------------
+								 *	T = alter column default
+								 *	N = alter column drop not null
+								 *	O = alter column set not null
+								 *	C = add constraint
+								 *	X = drop constraint
+								 *------------
+								 */
+	List	   *typeName;		/* domain to work on */
+	char	   *name;			/* column or constraint name to act on */
+	Node	   *def;			/* definition of default or constraint */
+	DropBehavior behavior;		/* RESTRICT or CASCADE for DROP cases */
+	bool		missing_ok;		/* skip error if missing? */
+} AlterDomainStmt;
+
+
+/* ----------------------
+ *		Grant|Revoke Statement
+ * ----------------------
+ */
+typedef enum GrantTargetType
+{
+	ACL_TARGET_OBJECT,			/* grant on specific named object(s) */
+	ACL_TARGET_ALL_IN_SCHEMA,	/* grant on all objects in given schema(s) */
+	ACL_TARGET_DEFAULTS			/* ALTER DEFAULT PRIVILEGES */
+} GrantTargetType;
+
+typedef struct GrantStmt
+{
+	NodeTag		type;
+	bool		is_grant;		/* true = GRANT, false = REVOKE */
+	GrantTargetType targtype;	/* type of the grant target */
+	ObjectType	objtype;		/* kind of object being operated on */
+	List	   *objects;		/* list of RangeVar nodes, ObjectWithArgs
+								 * nodes, or plain names (as Value strings) */
+	List	   *privileges;		/* list of AccessPriv nodes */
+	/* privileges == NIL denotes ALL PRIVILEGES */
+	List	   *grantees;		/* list of RoleSpec nodes */
+	bool		grant_option;	/* grant or revoke grant option */
+	DropBehavior behavior;		/* drop behavior (for REVOKE) */
+} GrantStmt;
+
+/*
+ * Note: ObjectWithArgs carries only the types of the input parameters of the
+ * function.  So it is sufficient to identify an existing function, but it
+ * is not enough info to define a function nor to call it.
+ */
+typedef struct ObjectWithArgs
+{
+	NodeTag		type;
+	List	   *objname;		/* qualified name of function/operator */
+	List	   *objargs;		/* list of Typename nodes */
+	bool		args_unspecified;	/* argument list was omitted, so name must
+									 * be unique (note that objargs == NIL
+									 * means zero args) */
+} ObjectWithArgs;
+
+/*
+ * An access privilege, with optional list of column names
+ * priv_name == NULL denotes ALL PRIVILEGES (only used with a column list)
+ * cols == NIL denotes "all columns"
+ * Note that simple "ALL PRIVILEGES" is represented as a NIL list, not
+ * an AccessPriv with both fields null.
+ */
+typedef struct AccessPriv
+{
+	NodeTag		type;
+	char	   *priv_name;		/* string name of privilege */
+	List	   *cols;			/* list of Value strings */
+} AccessPriv;
+
+/* ----------------------
+ *		Grant/Revoke Role Statement
+ *
+ * Note: because of the parsing ambiguity with the GRANT <privileges>
+ * statement, granted_roles is a list of AccessPriv; the execution code
+ * should complain if any column lists appear.  grantee_roles is a list
+ * of role names, as Value strings.
+ * ----------------------
+ */
+typedef struct GrantRoleStmt
+{
+	NodeTag		type;
+	List	   *granted_roles;	/* list of roles to be granted/revoked */
+	List	   *grantee_roles;	/* list of member roles to add/delete */
+	bool		is_grant;		/* true = GRANT, false = REVOKE */
+	bool		admin_opt;		/* with admin option */
+	RoleSpec   *grantor;		/* set grantor to other than current role */
+	DropBehavior behavior;		/* drop behavior (for REVOKE) */
+} GrantRoleStmt;
+
+/* ----------------------
+ *	Alter Default Privileges Statement
+ * ----------------------
+ */
+typedef struct AlterDefaultPrivilegesStmt
+{
+	NodeTag		type;
+	List	   *options;		/* list of DefElem */
+	GrantStmt  *action;			/* GRANT/REVOKE action (with objects=NIL) */
+} AlterDefaultPrivilegesStmt;
+
+/* ----------------------
+ *		Copy Statement
+ *
+ * We support "COPY relation FROM file", "COPY relation TO file", and
+ * "COPY (query) TO file".  In any given CopyStmt, exactly one of "relation"
+ * and "query" must be non-NULL.
+ * ----------------------
+ */
+typedef struct CopyStmt
+{
+	NodeTag		type;
+	RangeVar   *relation;		/* the relation to copy */
+	Node	   *query;			/* the query (SELECT or DML statement with
+								 * RETURNING) to copy, as a raw parse tree */
+	List	   *attlist;		/* List of column names (as Strings), or NIL
+								 * for all columns */
+	bool		is_from;		/* TO or FROM */
+	bool		is_program;		/* is 'filename' a program to popen? */
+	char	   *filename;		/* filename, or NULL for STDIN/STDOUT */
+	List	   *options;		/* List of DefElem nodes */
+	Node	   *whereClause;	/* WHERE condition (or NULL) */
+} CopyStmt;
+
+/* ----------------------
+ * SET Statement (includes RESET)
+ *
+ * "SET var TO DEFAULT" and "RESET var" are semantically equivalent, but we
+ * preserve the distinction in VariableSetKind for CreateCommandTag().
+ * ----------------------
+ */
+typedef enum
+{
+	VAR_SET_VALUE,				/* SET var = value */
+	VAR_SET_DEFAULT,			/* SET var TO DEFAULT */
+	VAR_SET_CURRENT,			/* SET var FROM CURRENT */
+	VAR_SET_MULTI,				/* special case for SET TRANSACTION ... */
+	VAR_RESET,					/* RESET var */
+	VAR_RESET_ALL				/* RESET ALL */
+} VariableSetKind;
+
+typedef struct VariableSetStmt
+{
+	NodeTag		type;
+	VariableSetKind kind;
+	char	   *name;			/* variable to be set */
+	List	   *args;			/* List of A_Const nodes */
+	bool		is_local;		/* SET LOCAL? */
+} VariableSetStmt;
+
+/* ----------------------
+ * Show Statement
+ * ----------------------
+ */
+typedef struct VariableShowStmt
+{
+	NodeTag		type;
+	char	   *name;
+} VariableShowStmt;
+
+/* ----------------------
+ *		Create Table Statement
+ *
+ * NOTE: in the raw gram.y output, ColumnDef and Constraint nodes are
+ * intermixed in tableElts, and constraints is NIL.  After parse analysis,
+ * tableElts contains just ColumnDefs, and constraints contains just
+ * Constraint nodes (in fact, only CONSTR_CHECK nodes, in the present
+ * implementation).
+ * ----------------------
+ */
+
+typedef struct CreateStmt
+{
+	NodeTag		type;
+	RangeVar   *relation;		/* relation to create */
+	List	   *tableElts;		/* column definitions (list of ColumnDef) */
+	List	   *inhRelations;	/* relations to inherit from (list of
+								 * inhRelation) */
+	PartitionBoundSpec *partbound;	/* FOR VALUES clause */
+	PartitionSpec *partspec;	/* PARTITION BY clause */
+	TypeName   *ofTypename;		/* OF typename */
+	List	   *constraints;	/* constraints (list of Constraint nodes) */
+	List	   *options;		/* options from WITH clause */
+	OnCommitAction oncommit;	/* what do we do at COMMIT? */
+	char	   *tablespacename; /* table space to use, or NULL */
+	char	   *accessMethod;	/* table access method */
+	bool		if_not_exists;	/* just do nothing if it already exists? */
+} CreateStmt;
+
+/* ----------
+ * Definitions for constraints in CreateStmt
+ *
+ * Note that column defaults are treated as a type of constraint,
+ * even though that's a bit odd semantically.
+ *
+ * For constraints that use expressions (CONSTR_CHECK, CONSTR_DEFAULT)
+ * we may have the expression in either "raw" form (an untransformed
+ * parse tree) or "cooked" form (the nodeToString representation of
+ * an executable expression tree), depending on how this Constraint
+ * node was created (by parsing, or by inheritance from an existing
+ * relation).  We should never have both in the same node!
+ *
+ * FKCONSTR_ACTION_xxx values are stored into pg_constraint.confupdtype
+ * and pg_constraint.confdeltype columns; FKCONSTR_MATCH_xxx values are
+ * stored into pg_constraint.confmatchtype.  Changing the code values may
+ * require an initdb!
+ *
+ * If skip_validation is true then we skip checking that the existing rows
+ * in the table satisfy the constraint, and just install the catalog entries
+ * for the constraint.  A new FK constraint is marked as valid iff
+ * initially_valid is true.  (Usually skip_validation and initially_valid
+ * are inverses, but we can set both true if the table is known empty.)
+ *
+ * Constraint attributes (DEFERRABLE etc) are initially represented as
+ * separate Constraint nodes for simplicity of parsing.  parse_utilcmd.c makes
+ * a pass through the constraints list to insert the info into the appropriate
+ * Constraint node.
+ * ----------
+ */
+
+typedef enum ConstrType			/* types of constraints */
+{
+	CONSTR_NULL,				/* not standard SQL, but a lot of people
+								 * expect it */
+	CONSTR_NOTNULL,
+	CONSTR_DEFAULT,
+	CONSTR_IDENTITY,
+	CONSTR_GENERATED,
+	CONSTR_CHECK,
+	CONSTR_PRIMARY,
+	CONSTR_UNIQUE,
+	CONSTR_EXCLUSION,
+	CONSTR_FOREIGN,
+	CONSTR_ATTR_DEFERRABLE,		/* attributes for previous constraint node */
+	CONSTR_ATTR_NOT_DEFERRABLE,
+	CONSTR_ATTR_DEFERRED,
+	CONSTR_ATTR_IMMEDIATE
+} ConstrType;
+
+/* Foreign key action codes */
+#define FKCONSTR_ACTION_NOACTION	'a'
+#define FKCONSTR_ACTION_RESTRICT	'r'
+#define FKCONSTR_ACTION_CASCADE		'c'
+#define FKCONSTR_ACTION_SETNULL		'n'
+#define FKCONSTR_ACTION_SETDEFAULT	'd'
+
+/* Foreign key matchtype codes */
+#define FKCONSTR_MATCH_FULL			'f'
+#define FKCONSTR_MATCH_PARTIAL		'p'
+#define FKCONSTR_MATCH_SIMPLE		's'
+
+typedef struct Constraint
+{
+	NodeTag		type;
+	ConstrType	contype;		/* see above */
+
+	/* Fields used for most/all constraint types: */
+	char	   *conname;		/* Constraint name, or NULL if unnamed */
+	bool		deferrable;		/* DEFERRABLE? */
+	bool		initdeferred;	/* INITIALLY DEFERRED? */
+	int			location;		/* token location, or -1 if unknown */
+
+	/* Fields used for constraints with expressions (CHECK and DEFAULT): */
+	bool		is_no_inherit;	/* is constraint non-inheritable? */
+	Node	   *raw_expr;		/* expr, as untransformed parse tree */
+	char	   *cooked_expr;	/* expr, as nodeToString representation */
+	char		generated_when; /* ALWAYS or BY DEFAULT */
+
+	/* Fields used for unique constraints (UNIQUE and PRIMARY KEY): */
+	List	   *keys;			/* String nodes naming referenced key
+								 * column(s) */
+	List	   *including;		/* String nodes naming referenced nonkey
+								 * column(s) */
+
+	/* Fields used for EXCLUSION constraints: */
+	List	   *exclusions;		/* list of (IndexElem, operator name) pairs */
+
+	/* Fields used for index constraints (UNIQUE, PRIMARY KEY, EXCLUSION): */
+	List	   *options;		/* options from WITH clause */
+	char	   *indexname;		/* existing index to use; otherwise NULL */
+	char	   *indexspace;		/* index tablespace; NULL for default */
+	bool		reset_default_tblspc;	/* reset default_tablespace prior to
+										 * creating the index */
+	/* These could be, but currently are not, used for UNIQUE/PKEY: */
+	char	   *access_method;	/* index access method; NULL for default */
+	Node	   *where_clause;	/* partial index predicate */
+
+	/* Fields used for FOREIGN KEY constraints: */
+	RangeVar   *pktable;		/* Primary key table */
+	List	   *fk_attrs;		/* Attributes of foreign key */
+	List	   *pk_attrs;		/* Corresponding attrs in PK table */
+	char		fk_matchtype;	/* FULL, PARTIAL, SIMPLE */
+	char		fk_upd_action;	/* ON UPDATE action */
+	char		fk_del_action;	/* ON DELETE action */
+	List	   *old_conpfeqop;	/* pg_constraint.conpfeqop of my former self */
+	Oid			old_pktable_oid;	/* pg_constraint.confrelid of my former
+									 * self */
+
+	/* Fields used for constraints that allow a NOT VALID specification */
+	bool		skip_validation;	/* skip validation of existing rows? */
+	bool		initially_valid;	/* mark the new constraint as valid? */
+} Constraint;
+
+/* ----------------------
+ *		Create/Drop Table Space Statements
+ * ----------------------
+ */
+
+typedef struct CreateTableSpaceStmt
+{
+	NodeTag		type;
+	char	   *tablespacename;
+	RoleSpec   *owner;
+	char	   *location;
+	List	   *options;
+} CreateTableSpaceStmt;
+
+typedef struct DropTableSpaceStmt
+{
+	NodeTag		type;
+	char	   *tablespacename;
+	bool		missing_ok;		/* skip error if missing? */
+} DropTableSpaceStmt;
+
+typedef struct AlterTableSpaceOptionsStmt
+{
+	NodeTag		type;
+	char	   *tablespacename;
+	List	   *options;
+	bool		isReset;
+} AlterTableSpaceOptionsStmt;
+
+typedef struct AlterTableMoveAllStmt
+{
+	NodeTag		type;
+	char	   *orig_tablespacename;
+	ObjectType	objtype;		/* Object type to move */
+	List	   *roles;			/* List of roles to move objects of */
+	char	   *new_tablespacename;
+	bool		nowait;
+} AlterTableMoveAllStmt;
+
+/* ----------------------
+ *		Create/Alter Extension Statements
+ * ----------------------
+ */
+
+typedef struct CreateExtensionStmt
+{
+	NodeTag		type;
+	char	   *extname;
+	bool		if_not_exists;	/* just do nothing if it already exists? */
+	List	   *options;		/* List of DefElem nodes */
+} CreateExtensionStmt;
+
+/* Only used for ALTER EXTENSION UPDATE; later might need an action field */
+typedef struct AlterExtensionStmt
+{
+	NodeTag		type;
+	char	   *extname;
+	List	   *options;		/* List of DefElem nodes */
+} AlterExtensionStmt;
+
+typedef struct AlterExtensionContentsStmt
+{
+	NodeTag		type;
+	char	   *extname;		/* Extension's name */
+	int			action;			/* +1 = add object, -1 = drop object */
+	ObjectType	objtype;		/* Object's type */
+	Node	   *object;			/* Qualified name of the object */
+} AlterExtensionContentsStmt;
+
+/* ----------------------
+ *		Create/Alter FOREIGN DATA WRAPPER Statements
+ * ----------------------
+ */
+
+typedef struct CreateFdwStmt
+{
+	NodeTag		type;
+	char	   *fdwname;		/* foreign-data wrapper name */
+	List	   *func_options;	/* HANDLER/VALIDATOR options */
+	List	   *options;		/* generic options to FDW */
+} CreateFdwStmt;
+
+typedef struct AlterFdwStmt
+{
+	NodeTag		type;
+	char	   *fdwname;		/* foreign-data wrapper name */
+	List	   *func_options;	/* HANDLER/VALIDATOR options */
+	List	   *options;		/* generic options to FDW */
+} AlterFdwStmt;
+
+/* ----------------------
+ *		Create/Alter FOREIGN SERVER Statements
+ * ----------------------
+ */
+
+typedef struct CreateForeignServerStmt
+{
+	NodeTag		type;
+	char	   *servername;		/* server name */
+	char	   *servertype;		/* optional server type */
+	char	   *version;		/* optional server version */
+	char	   *fdwname;		/* FDW name */
+	bool		if_not_exists;	/* just do nothing if it already exists? */
+	List	   *options;		/* generic options to server */
+} CreateForeignServerStmt;
+
+typedef struct AlterForeignServerStmt
+{
+	NodeTag		type;
+	char	   *servername;		/* server name */
+	char	   *version;		/* optional server version */
+	List	   *options;		/* generic options to server */
+	bool		has_version;	/* version specified */
+} AlterForeignServerStmt;
+
+/* ----------------------
+ *		Create FOREIGN TABLE Statement
+ * ----------------------
+ */
+
+typedef struct CreateForeignTableStmt
+{
+	CreateStmt	base;
+	char	   *servername;
+	List	   *options;
+} CreateForeignTableStmt;
+
+/* ----------------------
+ *		Create/Drop USER MAPPING Statements
+ * ----------------------
+ */
+
+typedef struct CreateUserMappingStmt
+{
+	NodeTag		type;
+	RoleSpec   *user;			/* user role */
+	char	   *servername;		/* server name */
+	bool		if_not_exists;	/* just do nothing if it already exists? */
+	List	   *options;		/* generic options to server */
+} CreateUserMappingStmt;
+
+typedef struct AlterUserMappingStmt
+{
+	NodeTag		type;
+	RoleSpec   *user;			/* user role */
+	char	   *servername;		/* server name */
+	List	   *options;		/* generic options to server */
+} AlterUserMappingStmt;
+
+typedef struct DropUserMappingStmt
+{
+	NodeTag		type;
+	RoleSpec   *user;			/* user role */
+	char	   *servername;		/* server name */
+	bool		missing_ok;		/* ignore missing mappings */
+} DropUserMappingStmt;
+
+/* ----------------------
+ *		Import Foreign Schema Statement
+ * ----------------------
+ */
+
+typedef enum ImportForeignSchemaType
+{
+	FDW_IMPORT_SCHEMA_ALL,		/* all relations wanted */
+	FDW_IMPORT_SCHEMA_LIMIT_TO, /* include only listed tables in import */
+	FDW_IMPORT_SCHEMA_EXCEPT	/* exclude listed tables from import */
+} ImportForeignSchemaType;
+
+typedef struct ImportForeignSchemaStmt
+{
+	NodeTag		type;
+	char	   *server_name;	/* FDW server name */
+	char	   *remote_schema;	/* remote schema name to query */
+	char	   *local_schema;	/* local schema to create objects in */
+	ImportForeignSchemaType list_type;	/* type of table list */
+	List	   *table_list;		/* List of RangeVar */
+	List	   *options;		/* list of options to pass to FDW */
+} ImportForeignSchemaStmt;
+
+/*----------------------
+ *		Create POLICY Statement
+ *----------------------
+ */
+typedef struct CreatePolicyStmt
+{
+	NodeTag		type;
+	char	   *policy_name;	/* Policy's name */
+	RangeVar   *table;			/* the table name the policy applies to */
+	char	   *cmd_name;		/* the command name the policy applies to */
+	bool		permissive;		/* restrictive or permissive policy */
+	List	   *roles;			/* the roles associated with the policy */
+	Node	   *qual;			/* the policy's condition */
+	Node	   *with_check;		/* the policy's WITH CHECK condition. */
+} CreatePolicyStmt;
+
+/*----------------------
+ *		Alter POLICY Statement
+ *----------------------
+ */
+typedef struct AlterPolicyStmt
+{
+	NodeTag		type;
+	char	   *policy_name;	/* Policy's name */
+	RangeVar   *table;			/* the table name the policy applies to */
+	List	   *roles;			/* the roles associated with the policy */
+	Node	   *qual;			/* the policy's condition */
+	Node	   *with_check;		/* the policy's WITH CHECK condition. */
+} AlterPolicyStmt;
+
+/*----------------------
+ *		Create ACCESS METHOD Statement
+ *----------------------
+ */
+typedef struct CreateAmStmt
+{
+	NodeTag		type;
+	char	   *amname;			/* access method name */
+	List	   *handler_name;	/* handler function name */
+	char		amtype;			/* type of access method */
+} CreateAmStmt;
+
+/* ----------------------
+ *		Create TRIGGER Statement
+ * ----------------------
+ */
+typedef struct CreateTrigStmt
+{
+	NodeTag		type;
+	char	   *trigname;		/* TRIGGER's name */
+	RangeVar   *relation;		/* relation trigger is on */
+	List	   *funcname;		/* qual. name of function to call */
+	List	   *args;			/* list of (T_String) Values or NIL */
+	bool		row;			/* ROW/STATEMENT */
+	/* timing uses the TRIGGER_TYPE bits defined in catalog/pg_trigger.h */
+	int16		timing;			/* BEFORE, AFTER, or INSTEAD */
+	/* events uses the TRIGGER_TYPE bits defined in catalog/pg_trigger.h */
+	int16		events;			/* "OR" of INSERT/UPDATE/DELETE/TRUNCATE */
+	List	   *columns;		/* column names, or NIL for all columns */
+	Node	   *whenClause;		/* qual expression, or NULL if none */
+	bool		isconstraint;	/* This is a constraint trigger */
+	/* explicitly named transition data */
+	List	   *transitionRels; /* TriggerTransition nodes, or NIL if none */
+	/* The remaining fields are only used for constraint triggers */
+	bool		deferrable;		/* [NOT] DEFERRABLE */
+	bool		initdeferred;	/* INITIALLY {DEFERRED|IMMEDIATE} */
+	RangeVar   *constrrel;		/* opposite relation, if RI trigger */
+} CreateTrigStmt;
+
+/* ----------------------
+ *		Create EVENT TRIGGER Statement
+ * ----------------------
+ */
+typedef struct CreateEventTrigStmt
+{
+	NodeTag		type;
+	char	   *trigname;		/* TRIGGER's name */
+	char	   *eventname;		/* event's identifier */
+	List	   *whenclause;		/* list of DefElems indicating filtering */
+	List	   *funcname;		/* qual. name of function to call */
+} CreateEventTrigStmt;
+
+/* ----------------------
+ *		Alter EVENT TRIGGER Statement
+ * ----------------------
+ */
+typedef struct AlterEventTrigStmt
+{
+	NodeTag		type;
+	char	   *trigname;		/* TRIGGER's name */
+	char		tgenabled;		/* trigger's firing configuration WRT
+								 * session_replication_role */
+} AlterEventTrigStmt;
+
+/* ----------------------
+ *		Create LANGUAGE Statements
+ * ----------------------
+ */
+typedef struct CreatePLangStmt
+{
+	NodeTag		type;
+	bool		replace;		/* T => replace if already exists */
+	char	   *plname;			/* PL name */
+	List	   *plhandler;		/* PL call handler function (qual. name) */
+	List	   *plinline;		/* optional inline function (qual. name) */
+	List	   *plvalidator;	/* optional validator function (qual. name) */
+	bool		pltrusted;		/* PL is trusted */
+} CreatePLangStmt;
+
+/* ----------------------
+ *	Create/Alter/Drop Role Statements
+ *
+ * Note: these node types are also used for the backwards-compatible
+ * Create/Alter/Drop User/Group statements.  In the ALTER and DROP cases
+ * there's really no need to distinguish what the original spelling was,
+ * but for CREATE we mark the type because the defaults vary.
+ * ----------------------
+ */
+typedef enum RoleStmtType
+{
+	ROLESTMT_ROLE,
+	ROLESTMT_USER,
+	ROLESTMT_GROUP
+} RoleStmtType;
+
+typedef struct CreateRoleStmt
+{
+	NodeTag		type;
+	RoleStmtType stmt_type;		/* ROLE/USER/GROUP */
+	char	   *role;			/* role name */
+	List	   *options;		/* List of DefElem nodes */
+} CreateRoleStmt;
+
+typedef struct AlterRoleStmt
+{
+	NodeTag		type;
+	RoleSpec   *role;			/* role */
+	List	   *options;		/* List of DefElem nodes */
+	int			action;			/* +1 = add members, -1 = drop members */
+} AlterRoleStmt;
+
+typedef struct AlterRoleSetStmt
+{
+	NodeTag		type;
+	RoleSpec   *role;			/* role */
+	char	   *database;		/* database name, or NULL */
+	VariableSetStmt *setstmt;	/* SET or RESET subcommand */
+} AlterRoleSetStmt;
+
+typedef struct DropRoleStmt
+{
+	NodeTag		type;
+	List	   *roles;			/* List of roles to remove */
+	bool		missing_ok;		/* skip error if a role is missing? */
+} DropRoleStmt;
+
+/* ----------------------
+ *		{Create|Alter} SEQUENCE Statement
+ * ----------------------
+ */
+
+typedef struct CreateSeqStmt
+{
+	NodeTag		type;
+	RangeVar   *sequence;		/* the sequence to create */
+	List	   *options;
+	Oid			ownerId;		/* ID of owner, or InvalidOid for default */
+	bool		for_identity;
+	bool		if_not_exists;	/* just do nothing if it already exists? */
+} CreateSeqStmt;
+
+typedef struct AlterSeqStmt
+{
+	NodeTag		type;
+	RangeVar   *sequence;		/* the sequence to alter */
+	List	   *options;
+	bool		for_identity;
+	bool		missing_ok;		/* skip error if a role is missing? */
+} AlterSeqStmt;
+
+/* ----------------------
+ *		Create {Aggregate|Operator|Type} Statement
+ * ----------------------
+ */
+typedef struct DefineStmt
+{
+	NodeTag		type;
+	ObjectType	kind;			/* aggregate, operator, type */
+	bool		oldstyle;		/* hack to signal old CREATE AGG syntax */
+	List	   *defnames;		/* qualified name (list of Value strings) */
+	List	   *args;			/* a list of TypeName (if needed) */
+	List	   *definition;		/* a list of DefElem */
+	bool		if_not_exists;	/* just do nothing if it already exists? */
+	bool		replace;		/* replace if already exists? */
+} DefineStmt;
+
+/* ----------------------
+ *		Create Domain Statement
+ * ----------------------
+ */
+typedef struct CreateDomainStmt
+{
+	NodeTag		type;
+	List	   *domainname;		/* qualified name (list of Value strings) */
+	TypeName   *typeName;		/* the base type */
+	CollateClause *collClause;	/* untransformed COLLATE spec, if any */
+	List	   *constraints;	/* constraints (list of Constraint nodes) */
+} CreateDomainStmt;
+
+/* ----------------------
+ *		Create Operator Class Statement
+ * ----------------------
+ */
+typedef struct CreateOpClassStmt
+{
+	NodeTag		type;
+	List	   *opclassname;	/* qualified name (list of Value strings) */
+	List	   *opfamilyname;	/* qualified name (ditto); NIL if omitted */
+	char	   *amname;			/* name of index AM opclass is for */
+	TypeName   *datatype;		/* datatype of indexed column */
+	List	   *items;			/* List of CreateOpClassItem nodes */
+	bool		isDefault;		/* Should be marked as default for type? */
+} CreateOpClassStmt;
+
+#define OPCLASS_ITEM_OPERATOR		1
+#define OPCLASS_ITEM_FUNCTION		2
+#define OPCLASS_ITEM_STORAGETYPE	3
+
+typedef struct CreateOpClassItem
+{
+	NodeTag		type;
+	int			itemtype;		/* see codes above */
+	ObjectWithArgs *name;		/* operator or function name and args */
+	int			number;			/* strategy num or support proc num */
+	List	   *order_family;	/* only used for ordering operators */
+	List	   *class_args;		/* amproclefttype/amprocrighttype or
+								 * amoplefttype/amoprighttype */
+	/* fields used for a storagetype item: */
+	TypeName   *storedtype;		/* datatype stored in index */
+} CreateOpClassItem;
+
+/* ----------------------
+ *		Create Operator Family Statement
+ * ----------------------
+ */
+typedef struct CreateOpFamilyStmt
+{
+	NodeTag		type;
+	List	   *opfamilyname;	/* qualified name (list of Value strings) */
+	char	   *amname;			/* name of index AM opfamily is for */
+} CreateOpFamilyStmt;
+
+/* ----------------------
+ *		Alter Operator Family Statement
+ * ----------------------
+ */
+typedef struct AlterOpFamilyStmt
+{
+	NodeTag		type;
+	List	   *opfamilyname;	/* qualified name (list of Value strings) */
+	char	   *amname;			/* name of index AM opfamily is for */
+	bool		isDrop;			/* ADD or DROP the items? */
+	List	   *items;			/* List of CreateOpClassItem nodes */
+} AlterOpFamilyStmt;
+
+/* ----------------------
+ *		Drop Table|Sequence|View|Index|Type|Domain|Conversion|Schema Statement
+ * ----------------------
+ */
+
+typedef struct DropStmt
+{
+	NodeTag		type;
+	List	   *objects;		/* list of names */
+	ObjectType	removeType;		/* object type */
+	DropBehavior behavior;		/* RESTRICT or CASCADE behavior */
+	bool		missing_ok;		/* skip error if object is missing? */
+	bool		concurrent;		/* drop index concurrently? */
+} DropStmt;
+
+/* ----------------------
+ *				Truncate Table Statement
+ * ----------------------
+ */
+typedef struct TruncateStmt
+{
+	NodeTag		type;
+	List	   *relations;		/* relations (RangeVars) to be truncated */
+	bool		restart_seqs;	/* restart owned sequences? */
+	DropBehavior behavior;		/* RESTRICT or CASCADE behavior */
+} TruncateStmt;
+
+/* ----------------------
+ *				Comment On Statement
+ * ----------------------
+ */
+typedef struct CommentStmt
+{
+	NodeTag		type;
+	ObjectType	objtype;		/* Object's type */
+	Node	   *object;			/* Qualified name of the object */
+	char	   *comment;		/* Comment to insert, or NULL to remove */
+} CommentStmt;
+
+/* ----------------------
+ *				SECURITY LABEL Statement
+ * ----------------------
+ */
+typedef struct SecLabelStmt
+{
+	NodeTag		type;
+	ObjectType	objtype;		/* Object's type */
+	Node	   *object;			/* Qualified name of the object */
+	char	   *provider;		/* Label provider (or NULL) */
+	char	   *label;			/* New security label to be assigned */
+} SecLabelStmt;
+
+/* ----------------------
+ *		Declare Cursor Statement
+ *
+ * The "query" field is initially a raw parse tree, and is converted to a
+ * Query node during parse analysis.  Note that rewriting and planning
+ * of the query are always postponed until execution.
+ * ----------------------
+ */
+#define CURSOR_OPT_BINARY		0x0001	/* BINARY */
+#define CURSOR_OPT_SCROLL		0x0002	/* SCROLL explicitly given */
+#define CURSOR_OPT_NO_SCROLL	0x0004	/* NO SCROLL explicitly given */
+#define CURSOR_OPT_INSENSITIVE	0x0008	/* INSENSITIVE */
+#define CURSOR_OPT_HOLD			0x0010	/* WITH HOLD */
+/* these planner-control flags do not correspond to any SQL grammar: */
+#define CURSOR_OPT_FAST_PLAN	0x0020	/* prefer fast-start plan */
+#define CURSOR_OPT_GENERIC_PLAN 0x0040	/* force use of generic plan */
+#define CURSOR_OPT_CUSTOM_PLAN	0x0080	/* force use of custom plan */
+#define CURSOR_OPT_PARALLEL_OK	0x0100	/* parallel mode OK */
+
+typedef struct DeclareCursorStmt
+{
+	NodeTag		type;
+	char	   *portalname;		/* name of the portal (cursor) */
+	int			options;		/* bitmask of options (see above) */
+	Node	   *query;			/* the query (see comments above) */
+} DeclareCursorStmt;
+
+/* ----------------------
+ *		Close Portal Statement
+ * ----------------------
+ */
+typedef struct ClosePortalStmt
+{
+	NodeTag		type;
+	char	   *portalname;		/* name of the portal (cursor) */
+	/* NULL means CLOSE ALL */
+} ClosePortalStmt;
+
+/* ----------------------
+ *		Fetch Statement (also Move)
+ * ----------------------
+ */
+typedef enum FetchDirection
+{
+	/* for these, howMany is how many rows to fetch; FETCH_ALL means ALL */
+	FETCH_FORWARD,
+	FETCH_BACKWARD,
+	/* for these, howMany indicates a position; only one row is fetched */
+	FETCH_ABSOLUTE,
+	FETCH_RELATIVE
+} FetchDirection;
+
+#define FETCH_ALL	LONG_MAX
+
+typedef struct FetchStmt
+{
+	NodeTag		type;
+	FetchDirection direction;	/* see above */
+	long		howMany;		/* number of rows, or position argument */
+	char	   *portalname;		/* name of portal (cursor) */
+	bool		ismove;			/* true if MOVE */
+} FetchStmt;
+
+/* ----------------------
+ *		Create Index Statement
+ *
+ * This represents creation of an index and/or an associated constraint.
+ * If isconstraint is true, we should create a pg_constraint entry along
+ * with the index.  But if indexOid isn't InvalidOid, we are not creating an
+ * index, just a UNIQUE/PKEY constraint using an existing index.  isconstraint
+ * must always be true in this case, and the fields describing the index
+ * properties are empty.
+ * ----------------------
+ */
+typedef struct IndexStmt
+{
+	NodeTag		type;
+	char	   *idxname;		/* name of new index, or NULL for default */
+	RangeVar   *relation;		/* relation to build index on */
+	char	   *accessMethod;	/* name of access method (eg. btree) */
+	char	   *tableSpace;		/* tablespace, or NULL for default */
+	List	   *indexParams;	/* columns to index: a list of IndexElem */
+	List	   *indexIncludingParams;	/* additional columns to index: a list
+										 * of IndexElem */
+	List	   *options;		/* WITH clause options: a list of DefElem */
+	Node	   *whereClause;	/* qualification (partial-index predicate) */
+	List	   *excludeOpNames; /* exclusion operator names, or NIL if none */
+	char	   *idxcomment;		/* comment to apply to index, or NULL */
+	Oid			indexOid;		/* OID of an existing index, if any */
+	Oid			oldNode;		/* relfilenode of existing storage, if any */
+	SubTransactionId oldCreateSubid;	/* rd_createSubid of oldNode */
+	SubTransactionId oldFirstRelfilenodeSubid;	/* rd_firstRelfilenodeSubid of
+												 * oldNode */
+	bool		unique;			/* is index unique? */
+	bool		primary;		/* is index a primary key? */
+	bool		isconstraint;	/* is it for a pkey/unique constraint? */
+	bool		deferrable;		/* is the constraint DEFERRABLE? */
+	bool		initdeferred;	/* is the constraint INITIALLY DEFERRED? */
+	bool		transformed;	/* true when transformIndexStmt is finished */
+	bool		concurrent;		/* should this be a concurrent index build? */
+	bool		if_not_exists;	/* just do nothing if index already exists? */
+	bool		reset_default_tblspc;	/* reset default_tablespace prior to
+										 * executing */
+} IndexStmt;
+
+/* ----------------------
+ *		Create Statistics Statement
+ * ----------------------
+ */
+typedef struct CreateStatsStmt
+{
+	NodeTag		type;
+	List	   *defnames;		/* qualified name (list of Value strings) */
+	List	   *stat_types;		/* stat types (list of Value strings) */
+	List	   *exprs;			/* expressions to build statistics on */
+	List	   *relations;		/* rels to build stats on (list of RangeVar) */
+	char	   *stxcomment;		/* comment to apply to stats, or NULL */
+	bool		if_not_exists;	/* do nothing if stats name already exists */
+} CreateStatsStmt;
+
+/* ----------------------
+ *		Alter Statistics Statement
+ * ----------------------
+ */
+typedef struct AlterStatsStmt
+{
+	NodeTag		type;
+	List	   *defnames;		/* qualified name (list of Value strings) */
+	int			stxstattarget;	/* statistics target */
+	bool		missing_ok;		/* skip error if statistics object is missing */
+} AlterStatsStmt;
+
+/* ----------------------
+ *		Create Function Statement
+ * ----------------------
+ */
+typedef struct CreateFunctionStmt
+{
+	NodeTag		type;
+	bool		is_procedure;	/* it's really CREATE PROCEDURE */
+	bool		replace;		/* T => replace if already exists */
+	List	   *funcname;		/* qualified name of function to create */
+	List	   *parameters;		/* a list of FunctionParameter */
+	TypeName   *returnType;		/* the return type */
+	List	   *options;		/* a list of DefElem */
+} CreateFunctionStmt;
+
+typedef enum FunctionParameterMode
+{
+	/* the assigned enum values appear in pg_proc, don't change 'em! */
+	FUNC_PARAM_IN = 'i',		/* input only */
+	FUNC_PARAM_OUT = 'o',		/* output only */
+	FUNC_PARAM_INOUT = 'b',		/* both */
+	FUNC_PARAM_VARIADIC = 'v',	/* variadic (always input) */
+	FUNC_PARAM_TABLE = 't'		/* table function output column */
+} FunctionParameterMode;
+
+typedef struct FunctionParameter
+{
+	NodeTag		type;
+	char	   *name;			/* parameter name, or NULL if not given */
+	TypeName   *argType;		/* TypeName for parameter type */
+	FunctionParameterMode mode; /* IN/OUT/etc */
+	Node	   *defexpr;		/* raw default expr, or NULL if not given */
+} FunctionParameter;
+
+typedef struct AlterFunctionStmt
+{
+	NodeTag		type;
+	ObjectType	objtype;
+	ObjectWithArgs *func;		/* name and args of function */
+	List	   *actions;		/* list of DefElem */
+} AlterFunctionStmt;
+
+/* ----------------------
+ *		DO Statement
+ *
+ * DoStmt is the raw parser output, InlineCodeBlock is the execution-time API
+ * ----------------------
+ */
+typedef struct DoStmt
+{
+	NodeTag		type;
+	List	   *args;			/* List of DefElem nodes */
+} DoStmt;
+
+typedef struct InlineCodeBlock
+{
+	NodeTag		type;
+	char	   *source_text;	/* source text of anonymous code block */
+	Oid			langOid;		/* OID of selected language */
+	bool		langIsTrusted;	/* trusted property of the language */
+	bool		atomic;			/* atomic execution context */
+} InlineCodeBlock;
+
+/* ----------------------
+ *		CALL statement
+ * ----------------------
+ */
+typedef struct CallStmt
+{
+	NodeTag		type;
+	FuncCall   *funccall;		/* from the parser */
+	FuncExpr   *funcexpr;		/* transformed */
+} CallStmt;
+
+typedef struct CallContext
+{
+	NodeTag		type;
+	bool		atomic;
+} CallContext;
+
+/* ----------------------
+ *		Alter Object Rename Statement
+ * ----------------------
+ */
+typedef struct RenameStmt
+{
+	NodeTag		type;
+	ObjectType	renameType;		/* OBJECT_TABLE, OBJECT_COLUMN, etc */
+	ObjectType	relationType;	/* if column name, associated relation type */
+	RangeVar   *relation;		/* in case it's a table */
+	Node	   *object;			/* in case it's some other object */
+	char	   *subname;		/* name of contained object (column, rule,
+								 * trigger, etc) */
+	char	   *newname;		/* the new name */
+	DropBehavior behavior;		/* RESTRICT or CASCADE behavior */
+	bool		missing_ok;		/* skip error if missing? */
+} RenameStmt;
+
+/* ----------------------
+ * ALTER object DEPENDS ON EXTENSION extname
+ * ----------------------
+ */
+typedef struct AlterObjectDependsStmt
+{
+	NodeTag		type;
+	ObjectType	objectType;		/* OBJECT_FUNCTION, OBJECT_TRIGGER, etc */
+	RangeVar   *relation;		/* in case a table is involved */
+	Node	   *object;			/* name of the object */
+	Value	   *extname;		/* extension name */
+	bool		remove;			/* set true to remove dep rather than add */
+} AlterObjectDependsStmt;
+
+/* ----------------------
+ *		ALTER object SET SCHEMA Statement
+ * ----------------------
+ */
+typedef struct AlterObjectSchemaStmt
+{
+	NodeTag		type;
+	ObjectType	objectType;		/* OBJECT_TABLE, OBJECT_TYPE, etc */
+	RangeVar   *relation;		/* in case it's a table */
+	Node	   *object;			/* in case it's some other object */
+	char	   *newschema;		/* the new schema */
+	bool		missing_ok;		/* skip error if missing? */
+} AlterObjectSchemaStmt;
+
+/* ----------------------
+ *		Alter Object Owner Statement
+ * ----------------------
+ */
+typedef struct AlterOwnerStmt
+{
+	NodeTag		type;
+	ObjectType	objectType;		/* OBJECT_TABLE, OBJECT_TYPE, etc */
+	RangeVar   *relation;		/* in case it's a table */
+	Node	   *object;			/* in case it's some other object */
+	RoleSpec   *newowner;		/* the new owner */
+} AlterOwnerStmt;
+
+/* ----------------------
+ *		Alter Operator Set ( this-n-that )
+ * ----------------------
+ */
+typedef struct AlterOperatorStmt
+{
+	NodeTag		type;
+	ObjectWithArgs *opername;	/* operator name and argument types */
+	List	   *options;		/* List of DefElem nodes */
+} AlterOperatorStmt;
+
+/* ------------------------
+ *		Alter Type Set ( this-n-that )
+ * ------------------------
+ */
+typedef struct AlterTypeStmt
+{
+	NodeTag		type;
+	List	   *typeName;		/* type name (possibly qualified) */
+	List	   *options;		/* List of DefElem nodes */
+} AlterTypeStmt;
+
+/* ----------------------
+ *		Create Rule Statement
+ * ----------------------
+ */
+typedef struct RuleStmt
+{
+	NodeTag		type;
+	RangeVar   *relation;		/* relation the rule is for */
+	char	   *rulename;		/* name of the rule */
+	Node	   *whereClause;	/* qualifications */
+	CmdType		event;			/* SELECT, INSERT, etc */
+	bool		instead;		/* is a 'do instead'? */
+	List	   *actions;		/* the action statements */
+	bool		replace;		/* OR REPLACE */
+} RuleStmt;
+
+/* ----------------------
+ *		Notify Statement
+ * ----------------------
+ */
+typedef struct NotifyStmt
+{
+	NodeTag		type;
+	char	   *conditionname;	/* condition name to notify */
+	char	   *payload;		/* the payload string, or NULL if none */
+} NotifyStmt;
+
+/* ----------------------
+ *		Listen Statement
+ * ----------------------
+ */
+typedef struct ListenStmt
+{
+	NodeTag		type;
+	char	   *conditionname;	/* condition name to listen on */
+} ListenStmt;
+
+/* ----------------------
+ *		Unlisten Statement
+ * ----------------------
+ */
+typedef struct UnlistenStmt
+{
+	NodeTag		type;
+	char	   *conditionname;	/* name to unlisten on, or NULL for all */
+} UnlistenStmt;
+
+/* ----------------------
+ *		{Begin|Commit|Rollback} Transaction Statement
+ * ----------------------
+ */
+typedef enum TransactionStmtKind
+{
+	TRANS_STMT_BEGIN,
+	TRANS_STMT_START,			/* semantically identical to BEGIN */
+	TRANS_STMT_COMMIT,
+	TRANS_STMT_ROLLBACK,
+	TRANS_STMT_SAVEPOINT,
+	TRANS_STMT_RELEASE,
+	TRANS_STMT_ROLLBACK_TO,
+	TRANS_STMT_PREPARE,
+	TRANS_STMT_COMMIT_PREPARED,
+	TRANS_STMT_ROLLBACK_PREPARED
+} TransactionStmtKind;
+
+typedef struct TransactionStmt
+{
+	NodeTag		type;
+	TransactionStmtKind kind;	/* see above */
+	List	   *options;		/* for BEGIN/START commands */
+	char	   *savepoint_name; /* for savepoint commands */
+	char	   *gid;			/* for two-phase-commit related commands */
+	bool		chain;			/* AND CHAIN option */
+} TransactionStmt;
+
+/* ----------------------
+ *		Create Type Statement, composite types
+ * ----------------------
+ */
+typedef struct CompositeTypeStmt
+{
+	NodeTag		type;
+	RangeVar   *typevar;		/* the composite type to be created */
+	List	   *coldeflist;		/* list of ColumnDef nodes */
+} CompositeTypeStmt;
+
+/* ----------------------
+ *		Create Type Statement, enum types
+ * ----------------------
+ */
+typedef struct CreateEnumStmt
+{
+	NodeTag		type;
+	List	   *typeName;		/* qualified name (list of Value strings) */
+	List	   *vals;			/* enum values (list of Value strings) */
+} CreateEnumStmt;
+
+/* ----------------------
+ *		Create Type Statement, range types
+ * ----------------------
+ */
+typedef struct CreateRangeStmt
+{
+	NodeTag		type;
+	List	   *typeName;		/* qualified name (list of Value strings) */
+	List	   *params;			/* range parameters (list of DefElem) */
+} CreateRangeStmt;
+
+/* ----------------------
+ *		Alter Type Statement, enum types
+ * ----------------------
+ */
+typedef struct AlterEnumStmt
+{
+	NodeTag		type;
+	List	   *typeName;		/* qualified name (list of Value strings) */
+	char	   *oldVal;			/* old enum value's name, if renaming */
+	char	   *newVal;			/* new enum value's name */
+	char	   *newValNeighbor; /* neighboring enum value, if specified */
+	bool		newValIsAfter;	/* place new enum value after neighbor? */
+	bool		skipIfNewValExists; /* no error if new already exists? */
+} AlterEnumStmt;
+
+/* ----------------------
+ *		Create View Statement
+ * ----------------------
+ */
+typedef enum ViewCheckOption
+{
+	NO_CHECK_OPTION,
+	LOCAL_CHECK_OPTION,
+	CASCADED_CHECK_OPTION
+} ViewCheckOption;
+
+typedef struct ViewStmt
+{
+	NodeTag		type;
+	RangeVar   *view;			/* the view to be created */
+	List	   *aliases;		/* target column names */
+	Node	   *query;			/* the SELECT query (as a raw parse tree) */
+	bool		replace;		/* replace an existing view? */
+	List	   *options;		/* options from WITH clause */
+	ViewCheckOption withCheckOption;	/* WITH CHECK OPTION */
+} ViewStmt;
+
+/* ----------------------
+ *		Load Statement
+ * ----------------------
+ */
+typedef struct LoadStmt
+{
+	NodeTag		type;
+	char	   *filename;		/* file to load */
+} LoadStmt;
+
+/* ----------------------
+ *		Createdb Statement
+ * ----------------------
+ */
+typedef struct CreatedbStmt
+{
+	NodeTag		type;
+	char	   *dbname;			/* name of database to create */
+	List	   *options;		/* List of DefElem nodes */
+} CreatedbStmt;
+
+/* ----------------------
+ *	Alter Database
+ * ----------------------
+ */
+typedef struct AlterDatabaseStmt
+{
+	NodeTag		type;
+	char	   *dbname;			/* name of database to alter */
+	List	   *options;		/* List of DefElem nodes */
+} AlterDatabaseStmt;
+
+typedef struct AlterDatabaseSetStmt
+{
+	NodeTag		type;
+	char	   *dbname;			/* database name */
+	VariableSetStmt *setstmt;	/* SET or RESET subcommand */
+} AlterDatabaseSetStmt;
+
+/* ----------------------
+ *		Dropdb Statement
+ * ----------------------
+ */
+typedef struct DropdbStmt
+{
+	NodeTag		type;
+	char	   *dbname;			/* database to drop */
+	bool		missing_ok;		/* skip error if db is missing? */
+	List	   *options;		/* currently only FORCE is supported */
+} DropdbStmt;
+
+/* ----------------------
+ *		Alter System Statement
+ * ----------------------
+ */
+typedef struct AlterSystemStmt
+{
+	NodeTag		type;
+	VariableSetStmt *setstmt;	/* SET subcommand */
+} AlterSystemStmt;
+
+/* ----------------------
+ *		Cluster Statement (support pbrown's cluster index implementation)
+ * ----------------------
+ */
+typedef enum ClusterOption
+{
+	CLUOPT_RECHECK = 1 << 0,	/* recheck relation state */
+	CLUOPT_VERBOSE = 1 << 1		/* print progress info */
+} ClusterOption;
+
+typedef struct ClusterStmt
+{
+	NodeTag		type;
+	RangeVar   *relation;		/* relation being indexed, or NULL if all */
+	char	   *indexname;		/* original index defined */
+	int			options;		/* OR of ClusterOption flags */
+} ClusterStmt;
+
+/* ----------------------
+ *		Vacuum and Analyze Statements
+ *
+ * Even though these are nominally two statements, it's convenient to use
+ * just one node type for both.
+ * ----------------------
+ */
+typedef struct VacuumStmt
+{
+	NodeTag		type;
+	List	   *options;		/* list of DefElem nodes */
+	List	   *rels;			/* list of VacuumRelation, or NIL for all */
+	bool		is_vacuumcmd;	/* true for VACUUM, false for ANALYZE */
+} VacuumStmt;
+
+/*
+ * Info about a single target table of VACUUM/ANALYZE.
+ *
+ * If the OID field is set, it always identifies the table to process.
+ * Then the relation field can be NULL; if it isn't, it's used only to report
+ * failure to open/lock the relation.
+ */
+typedef struct VacuumRelation
+{
+	NodeTag		type;
+	RangeVar   *relation;		/* table name to process, or NULL */
+	Oid			oid;			/* table's OID; InvalidOid if not looked up */
+	List	   *va_cols;		/* list of column names, or NIL for all */
+} VacuumRelation;
+
+/* ----------------------
+ *		Explain Statement
+ *
+ * The "query" field is initially a raw parse tree, and is converted to a
+ * Query node during parse analysis.  Note that rewriting and planning
+ * of the query are always postponed until execution.
+ * ----------------------
+ */
+typedef struct ExplainStmt
+{
+	NodeTag		type;
+	Node	   *query;			/* the query (see comments above) */
+	List	   *options;		/* list of DefElem nodes */
+} ExplainStmt;
+
+/* ----------------------
+ *		CREATE TABLE AS Statement (a/k/a SELECT INTO)
+ *
+ * A query written as CREATE TABLE AS will produce this node type natively.
+ * A query written as SELECT ... INTO will be transformed to this form during
+ * parse analysis.
+ * A query written as CREATE MATERIALIZED view will produce this node type,
+ * during parse analysis, since it needs all the same data.
+ *
+ * The "query" field is handled similarly to EXPLAIN, though note that it
+ * can be a SELECT or an EXECUTE, but not other DML statements.
+ * ----------------------
+ */
+typedef struct CreateTableAsStmt
+{
+	NodeTag		type;
+	Node	   *query;			/* the query (see comments above) */
+	IntoClause *into;			/* destination table */
+	ObjectType	relkind;		/* OBJECT_TABLE or OBJECT_MATVIEW */
+	bool		is_select_into; /* it was written as SELECT INTO */
+	bool		if_not_exists;	/* just do nothing if it already exists? */
+} CreateTableAsStmt;
+
+/* ----------------------
+ *		REFRESH MATERIALIZED VIEW Statement
+ * ----------------------
+ */
+typedef struct RefreshMatViewStmt
+{
+	NodeTag		type;
+	bool		concurrent;		/* allow concurrent access? */
+	bool		skipData;		/* true for WITH NO DATA */
+	RangeVar   *relation;		/* relation to insert into */
+} RefreshMatViewStmt;
+
+/* ----------------------
+ * Checkpoint Statement
+ * ----------------------
+ */
+typedef struct CheckPointStmt
+{
+	NodeTag		type;
+} CheckPointStmt;
+
+/* ----------------------
+ * Discard Statement
+ * ----------------------
+ */
+
+typedef enum DiscardMode
+{
+	DISCARD_ALL,
+	DISCARD_PLANS,
+	DISCARD_SEQUENCES,
+	DISCARD_TEMP
+} DiscardMode;
+
+typedef struct DiscardStmt
+{
+	NodeTag		type;
+	DiscardMode target;
+} DiscardStmt;
+
+/* ----------------------
+ *		LOCK Statement
+ * ----------------------
+ */
+typedef struct LockStmt
+{
+	NodeTag		type;
+	List	   *relations;		/* relations to lock */
+	int			mode;			/* lock mode */
+	bool		nowait;			/* no wait mode */
+} LockStmt;
+
+/* ----------------------
+ *		SET CONSTRAINTS Statement
+ * ----------------------
+ */
+typedef struct ConstraintsSetStmt
+{
+	NodeTag		type;
+	List	   *constraints;	/* List of names as RangeVars */
+	bool		deferred;
+} ConstraintsSetStmt;
+
+/* ----------------------
+ *		REINDEX Statement
+ * ----------------------
+ */
+
+/* Reindex options */
+#define REINDEXOPT_VERBOSE (1 << 0) /* print progress info */
+#define REINDEXOPT_REPORT_PROGRESS (1 << 1) /* report pgstat progress */
+
+typedef enum ReindexObjectType
+{
+	REINDEX_OBJECT_INDEX,		/* index */
+	REINDEX_OBJECT_TABLE,		/* table or materialized view */
+	REINDEX_OBJECT_SCHEMA,		/* schema */
+	REINDEX_OBJECT_SYSTEM,		/* system catalogs */
+	REINDEX_OBJECT_DATABASE		/* database */
+} ReindexObjectType;
+
+typedef struct ReindexStmt
+{
+	NodeTag		type;
+	ReindexObjectType kind;		/* REINDEX_OBJECT_INDEX, REINDEX_OBJECT_TABLE,
+								 * etc. */
+	RangeVar   *relation;		/* Table or index to reindex */
+	const char *name;			/* name of database to reindex */
+	int			options;		/* Reindex options flags */
+	bool		concurrent;		/* reindex concurrently? */
+} ReindexStmt;
+
+/* ----------------------
+ *		CREATE CONVERSION Statement
+ * ----------------------
+ */
+typedef struct CreateConversionStmt
+{
+	NodeTag		type;
+	List	   *conversion_name;	/* Name of the conversion */
+	char	   *for_encoding_name;	/* source encoding name */
+	char	   *to_encoding_name;	/* destination encoding name */
+	List	   *func_name;		/* qualified conversion function name */
+	bool		def;			/* is this a default conversion? */
+} CreateConversionStmt;
+
+/* ----------------------
+ *	CREATE CAST Statement
+ * ----------------------
+ */
+typedef struct CreateCastStmt
+{
+	NodeTag		type;
+	TypeName   *sourcetype;
+	TypeName   *targettype;
+	ObjectWithArgs *func;
+	CoercionContext context;
+	bool		inout;
+} CreateCastStmt;
+
+/* ----------------------
+ *	CREATE TRANSFORM Statement
+ * ----------------------
+ */
+typedef struct CreateTransformStmt
+{
+	NodeTag		type;
+	bool		replace;
+	TypeName   *type_name;
+	char	   *lang;
+	ObjectWithArgs *fromsql;
+	ObjectWithArgs *tosql;
+} CreateTransformStmt;
+
+/* ----------------------
+ *		PREPARE Statement
+ * ----------------------
+ */
+typedef struct PrepareStmt
+{
+	NodeTag		type;
+	char	   *name;			/* Name of plan, arbitrary */
+	List	   *argtypes;		/* Types of parameters (List of TypeName) */
+	Node	   *query;			/* The query itself (as a raw parsetree) */
+} PrepareStmt;
+
+
+/* ----------------------
+ *		EXECUTE Statement
+ * ----------------------
+ */
+
+typedef struct ExecuteStmt
+{
+	NodeTag		type;
+	char	   *name;			/* The name of the plan to execute */
+	List	   *params;			/* Values to assign to parameters */
+} ExecuteStmt;
+
+
+/* ----------------------
+ *		DEALLOCATE Statement
+ * ----------------------
+ */
+typedef struct DeallocateStmt
+{
+	NodeTag		type;
+	char	   *name;			/* The name of the plan to remove */
+	/* NULL means DEALLOCATE ALL */
+} DeallocateStmt;
+
+/*
+ *		DROP OWNED statement
+ */
+typedef struct DropOwnedStmt
+{
+	NodeTag		type;
+	List	   *roles;
+	DropBehavior behavior;
+} DropOwnedStmt;
+
+/*
+ *		REASSIGN OWNED statement
+ */
+typedef struct ReassignOwnedStmt
+{
+	NodeTag		type;
+	List	   *roles;
+	RoleSpec   *newrole;
+} ReassignOwnedStmt;
+
+/*
+ * TS Dictionary stmts: DefineStmt, RenameStmt and DropStmt are default
+ */
+typedef struct AlterTSDictionaryStmt
+{
+	NodeTag		type;
+	List	   *dictname;		/* qualified name (list of Value strings) */
+	List	   *options;		/* List of DefElem nodes */
+} AlterTSDictionaryStmt;
+
+/*
+ * TS Configuration stmts: DefineStmt, RenameStmt and DropStmt are default
+ */
+typedef enum AlterTSConfigType
+{
+	ALTER_TSCONFIG_ADD_MAPPING,
+	ALTER_TSCONFIG_ALTER_MAPPING_FOR_TOKEN,
+	ALTER_TSCONFIG_REPLACE_DICT,
+	ALTER_TSCONFIG_REPLACE_DICT_FOR_TOKEN,
+	ALTER_TSCONFIG_DROP_MAPPING
+} AlterTSConfigType;
+
+typedef struct AlterTSConfigurationStmt
+{
+	NodeTag		type;
+	AlterTSConfigType kind;		/* ALTER_TSCONFIG_ADD_MAPPING, etc */
+	List	   *cfgname;		/* qualified name (list of Value strings) */
+
+	/*
+	 * dicts will be non-NIL if ADD/ALTER MAPPING was specified. If dicts is
+	 * NIL, but tokentype isn't, DROP MAPPING was specified.
+	 */
+	List	   *tokentype;		/* list of Value strings */
+	List	   *dicts;			/* list of list of Value strings */
+	bool		override;		/* if true - remove old variant */
+	bool		replace;		/* if true - replace dictionary by another */
+	bool		missing_ok;		/* for DROP - skip error if missing? */
+} AlterTSConfigurationStmt;
+
+
+typedef struct CreatePublicationStmt
+{
+	NodeTag		type;
+	char	   *pubname;		/* Name of the publication */
+	List	   *options;		/* List of DefElem nodes */
+	List	   *tables;			/* Optional list of tables to add */
+	bool		for_all_tables; /* Special publication for all tables in db */
+} CreatePublicationStmt;
+
+typedef struct AlterPublicationStmt
+{
+	NodeTag		type;
+	char	   *pubname;		/* Name of the publication */
+
+	/* parameters used for ALTER PUBLICATION ... WITH */
+	List	   *options;		/* List of DefElem nodes */
+
+	/* parameters used for ALTER PUBLICATION ... ADD/DROP TABLE */
+	List	   *tables;			/* List of tables to add/drop */
+	bool		for_all_tables; /* Special publication for all tables in db */
+	DefElemAction tableAction;	/* What action to perform with the tables */
+} AlterPublicationStmt;
+
+typedef struct CreateSubscriptionStmt
+{
+	NodeTag		type;
+	char	   *subname;		/* Name of the subscription */
+	char	   *conninfo;		/* Connection string to publisher */
+	List	   *publication;	/* One or more publication to subscribe to */
+	List	   *options;		/* List of DefElem nodes */
+} CreateSubscriptionStmt;
+
+typedef enum AlterSubscriptionType
+{
+	ALTER_SUBSCRIPTION_OPTIONS,
+	ALTER_SUBSCRIPTION_CONNECTION,
+	ALTER_SUBSCRIPTION_PUBLICATION,
+	ALTER_SUBSCRIPTION_REFRESH,
+	ALTER_SUBSCRIPTION_ENABLED
+} AlterSubscriptionType;
+
+typedef struct AlterSubscriptionStmt
+{
+	NodeTag		type;
+	AlterSubscriptionType kind; /* ALTER_SUBSCRIPTION_OPTIONS, etc */
+	char	   *subname;		/* Name of the subscription */
+	char	   *conninfo;		/* Connection string to publisher */
+	List	   *publication;	/* One or more publication to subscribe to */
+	List	   *options;		/* List of DefElem nodes */
+} AlterSubscriptionStmt;
+
+typedef struct DropSubscriptionStmt
+{
+	NodeTag		type;
+	char	   *subname;		/* Name of the subscription */
+	bool		missing_ok;		/* Skip error if missing? */
+	DropBehavior behavior;		/* RESTRICT or CASCADE behavior */
+} DropSubscriptionStmt;
+
+#endif							/* PARSENODES_H */
diff --git a/src/include/nodes/pathnodes.h b/src/include/nodes/pathnodes.h
new file mode 100644
index 0000000..69150e4
--- /dev/null
+++ b/src/include/nodes/pathnodes.h
@@ -0,0 +1,2556 @@
+/*-------------------------------------------------------------------------
+ *
+ * pathnodes.h
+ *	  Definitions for planner's internal data structures, especially Paths.
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/pathnodes.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef PATHNODES_H
+#define PATHNODES_H
+
+#include "access/sdir.h"
+#include "lib/stringinfo.h"
+#include "nodes/params.h"
+#include "nodes/parsenodes.h"
+#include "storage/block.h"
+
+
+/*
+ * Relids
+ *		Set of relation identifiers (indexes into the rangetable).
+ */
+typedef Bitmapset *Relids;
+
+/*
+ * When looking for a "cheapest path", this enum specifies whether we want
+ * cheapest startup cost or cheapest total cost.
+ */
+typedef enum CostSelector
+{
+	STARTUP_COST, TOTAL_COST
+} CostSelector;
+
+/*
+ * The cost estimate produced by cost_qual_eval() includes both a one-time
+ * (startup) cost, and a per-tuple cost.
+ */
+typedef struct QualCost
+{
+	Cost		startup;		/* one-time cost */
+	Cost		per_tuple;		/* per-evaluation cost */
+} QualCost;
+
+/*
+ * Costing aggregate function execution requires these statistics about
+ * the aggregates to be executed by a given Agg node.  Note that the costs
+ * include the execution costs of the aggregates' argument expressions as
+ * well as the aggregate functions themselves.  Also, the fields must be
+ * defined so that initializing the struct to zeroes with memset is correct.
+ */
+typedef struct AggClauseCosts
+{
+	int			numAggs;		/* total number of aggregate functions */
+	int			numOrderedAggs; /* number w/ DISTINCT/ORDER BY/WITHIN GROUP */
+	bool		hasNonPartial;	/* does any agg not support partial mode? */
+	bool		hasNonSerial;	/* is any partial agg non-serializable? */
+	QualCost	transCost;		/* total per-input-row execution costs */
+	QualCost	finalCost;		/* total per-aggregated-row costs */
+	Size		transitionSpace;	/* space for pass-by-ref transition data */
+} AggClauseCosts;
+
+/*
+ * This enum identifies the different types of "upper" (post-scan/join)
+ * relations that we might deal with during planning.
+ */
+typedef enum UpperRelationKind
+{
+	UPPERREL_SETOP,				/* result of UNION/INTERSECT/EXCEPT, if any */
+	UPPERREL_PARTIAL_GROUP_AGG, /* result of partial grouping/aggregation, if
+								 * any */
+	UPPERREL_GROUP_AGG,			/* result of grouping/aggregation, if any */
+	UPPERREL_WINDOW,			/* result of window functions, if any */
+	UPPERREL_DISTINCT,			/* result of "SELECT DISTINCT", if any */
+	UPPERREL_ORDERED,			/* result of ORDER BY, if any */
+	UPPERREL_FINAL				/* result of any remaining top-level actions */
+	/* NB: UPPERREL_FINAL must be last enum entry; it's used to size arrays */
+} UpperRelationKind;
+
+/*
+ * This enum identifies which type of relation is being planned through the
+ * inheritance planner.  INHKIND_NONE indicates the inheritance planner
+ * was not used.
+ */
+typedef enum InheritanceKind
+{
+	INHKIND_NONE,
+	INHKIND_INHERITED,
+	INHKIND_PARTITIONED
+} InheritanceKind;
+
+/*----------
+ * PlannerGlobal
+ *		Global information for planning/optimization
+ *
+ * PlannerGlobal holds state for an entire planner invocation; this state
+ * is shared across all levels of sub-Queries that exist in the command being
+ * planned.
+ *----------
+ */
+typedef struct PlannerGlobal
+{
+	NodeTag		type;
+
+	ParamListInfo boundParams;	/* Param values provided to planner() */
+
+	List	   *subplans;		/* Plans for SubPlan nodes */
+
+	List	   *subroots;		/* PlannerInfos for SubPlan nodes */
+
+	Bitmapset  *rewindPlanIDs;	/* indices of subplans that require REWIND */
+
+	List	   *finalrtable;	/* "flat" rangetable for executor */
+
+	List	   *finalrowmarks;	/* "flat" list of PlanRowMarks */
+
+	List	   *resultRelations;	/* "flat" list of integer RT indexes */
+
+	List	   *rootResultRelations;	/* "flat" list of integer RT indexes */
+
+	List	   *appendRelations;	/* "flat" list of AppendRelInfos */
+
+	List	   *relationOids;	/* OIDs of relations the plan depends on */
+
+	List	   *invalItems;		/* other dependencies, as PlanInvalItems */
+
+	List	   *paramExecTypes; /* type OIDs for PARAM_EXEC Params */
+
+	Index		lastPHId;		/* highest PlaceHolderVar ID assigned */
+
+	Index		lastRowMarkId;	/* highest PlanRowMark ID assigned */
+
+	int			lastPlanNodeId; /* highest plan node ID assigned */
+
+	bool		transientPlan;	/* redo plan when TransactionXmin changes? */
+
+	bool		dependsOnRole;	/* is plan specific to current role? */
+
+	bool		parallelModeOK; /* parallel mode potentially OK? */
+
+	bool		parallelModeNeeded; /* parallel mode actually required? */
+
+	char		maxParallelHazard;	/* worst PROPARALLEL hazard level */
+
+	PartitionDirectory partition_directory; /* partition descriptors */
+} PlannerGlobal;
+
+/* macro for fetching the Plan associated with a SubPlan node */
+#define planner_subplan_get_plan(root, subplan) \
+	((Plan *) list_nth((root)->glob->subplans, (subplan)->plan_id - 1))
+
+
+/*----------
+ * PlannerInfo
+ *		Per-query information for planning/optimization
+ *
+ * This struct is conventionally called "root" in all the planner routines.
+ * It holds links to all of the planner's working state, in addition to the
+ * original Query.  Note that at present the planner extensively modifies
+ * the passed-in Query data structure; someday that should stop.
+ *
+ * For reasons explained in optimizer/optimizer.h, we define the typedef
+ * either here or in that header, whichever is read first.
+ *----------
+ */
+#ifndef HAVE_PLANNERINFO_TYPEDEF
+typedef struct PlannerInfo PlannerInfo;
+#define HAVE_PLANNERINFO_TYPEDEF 1
+#endif
+
+struct PlannerInfo
+{
+	NodeTag		type;
+
+	Query	   *parse;			/* the Query being planned */
+
+	PlannerGlobal *glob;		/* global info for current planner run */
+
+	Index		query_level;	/* 1 at the outermost Query */
+
+	PlannerInfo *parent_root;	/* NULL at outermost Query */
+
+	/*
+	 * plan_params contains the expressions that this query level needs to
+	 * make available to a lower query level that is currently being planned.
+	 * outer_params contains the paramIds of PARAM_EXEC Params that outer
+	 * query levels will make available to this query level.
+	 */
+	List	   *plan_params;	/* list of PlannerParamItems, see below */
+	Bitmapset  *outer_params;
+
+	/*
+	 * simple_rel_array holds pointers to "base rels" and "other rels" (see
+	 * comments for RelOptInfo for more info).  It is indexed by rangetable
+	 * index (so entry 0 is always wasted).  Entries can be NULL when an RTE
+	 * does not correspond to a base relation, such as a join RTE or an
+	 * unreferenced view RTE; or if the RelOptInfo hasn't been made yet.
+	 */
+	struct RelOptInfo **simple_rel_array;	/* All 1-rel RelOptInfos */
+	int			simple_rel_array_size;	/* allocated size of array */
+
+	/*
+	 * simple_rte_array is the same length as simple_rel_array and holds
+	 * pointers to the associated rangetable entries.  Using this is a shade
+	 * faster than using rt_fetch(), mostly due to fewer indirections.
+	 */
+	RangeTblEntry **simple_rte_array;	/* rangetable as an array */
+
+	/*
+	 * append_rel_array is the same length as the above arrays, and holds
+	 * pointers to the corresponding AppendRelInfo entry indexed by
+	 * child_relid, or NULL if the rel is not an appendrel child.  The array
+	 * itself is not allocated if append_rel_list is empty.
+	 */
+	struct AppendRelInfo **append_rel_array;
+
+	/*
+	 * all_baserels is a Relids set of all base relids (but not "other"
+	 * relids) in the query; that is, the Relids identifier of the final join
+	 * we need to form.  This is computed in make_one_rel, just before we
+	 * start making Paths.
+	 */
+	Relids		all_baserels;
+
+	/*
+	 * nullable_baserels is a Relids set of base relids that are nullable by
+	 * some outer join in the jointree; these are rels that are potentially
+	 * nullable below the WHERE clause, SELECT targetlist, etc.  This is
+	 * computed in deconstruct_jointree.
+	 */
+	Relids		nullable_baserels;
+
+	/*
+	 * join_rel_list is a list of all join-relation RelOptInfos we have
+	 * considered in this planning run.  For small problems we just scan the
+	 * list to do lookups, but when there are many join relations we build a
+	 * hash table for faster lookups.  The hash table is present and valid
+	 * when join_rel_hash is not NULL.  Note that we still maintain the list
+	 * even when using the hash table for lookups; this simplifies life for
+	 * GEQO.
+	 */
+	List	   *join_rel_list;	/* list of join-relation RelOptInfos */
+	struct HTAB *join_rel_hash; /* optional hashtable for join relations */
+
+	/*
+	 * When doing a dynamic-programming-style join search, join_rel_level[k]
+	 * is a list of all join-relation RelOptInfos of level k, and
+	 * join_cur_level is the current level.  New join-relation RelOptInfos are
+	 * automatically added to the join_rel_level[join_cur_level] list.
+	 * join_rel_level is NULL if not in use.
+	 */
+	List	  **join_rel_level; /* lists of join-relation RelOptInfos */
+	int			join_cur_level; /* index of list being extended */
+
+	List	   *init_plans;		/* init SubPlans for query */
+
+	List	   *cte_plan_ids;	/* per-CTE-item list of subplan IDs */
+
+	List	   *multiexpr_params;	/* List of Lists of Params for MULTIEXPR
+									 * subquery outputs */
+
+	List	   *eq_classes;		/* list of active EquivalenceClasses */
+
+	bool		ec_merging_done;	/* set true once ECs are canonical */
+
+	List	   *canon_pathkeys; /* list of "canonical" PathKeys */
+
+	List	   *left_join_clauses;	/* list of RestrictInfos for mergejoinable
+									 * outer join clauses w/nonnullable var on
+									 * left */
+
+	List	   *right_join_clauses; /* list of RestrictInfos for mergejoinable
+									 * outer join clauses w/nonnullable var on
+									 * right */
+
+	List	   *full_join_clauses;	/* list of RestrictInfos for mergejoinable
+									 * full join clauses */
+
+	List	   *join_info_list; /* list of SpecialJoinInfos */
+
+	/*
+	 * Note: for AppendRelInfos describing partitions of a partitioned table,
+	 * we guarantee that partitions that come earlier in the partitioned
+	 * table's PartitionDesc will appear earlier in append_rel_list.
+	 */
+	List	   *append_rel_list;	/* list of AppendRelInfos */
+
+	List	   *rowMarks;		/* list of PlanRowMarks */
+
+	List	   *placeholder_list;	/* list of PlaceHolderInfos */
+
+	List	   *fkey_list;		/* list of ForeignKeyOptInfos */
+
+	List	   *query_pathkeys; /* desired pathkeys for query_planner() */
+
+	List	   *group_pathkeys; /* groupClause pathkeys, if any */
+	List	   *window_pathkeys;	/* pathkeys of bottom window, if any */
+	List	   *distinct_pathkeys;	/* distinctClause pathkeys, if any */
+	List	   *sort_pathkeys;	/* sortClause pathkeys, if any */
+
+	List	   *part_schemes;	/* Canonicalised partition schemes used in the
+								 * query. */
+
+	List	   *initial_rels;	/* RelOptInfos we are now trying to join */
+
+	/* Use fetch_upper_rel() to get any particular upper rel */
+	List	   *upper_rels[UPPERREL_FINAL + 1]; /* upper-rel RelOptInfos */
+
+	/* Result tlists chosen by grouping_planner for upper-stage processing */
+	struct PathTarget *upper_targets[UPPERREL_FINAL + 1];
+
+	/*
+	 * The fully-processed targetlist is kept here.  It differs from
+	 * parse->targetList in that (for INSERT and UPDATE) it's been reordered
+	 * to match the target table, and defaults have been filled in.  Also,
+	 * additional resjunk targets may be present.  preprocess_targetlist()
+	 * does most of this work, but note that more resjunk targets can get
+	 * added during appendrel expansion.  (Hence, upper_targets mustn't get
+	 * set up till after that.)
+	 */
+	List	   *processed_tlist;
+
+	/* Fields filled during create_plan() for use in setrefs.c */
+	AttrNumber *grouping_map;	/* for GroupingFunc fixup */
+	List	   *minmax_aggs;	/* List of MinMaxAggInfos */
+
+	MemoryContext planner_cxt;	/* context holding PlannerInfo */
+
+	double		total_table_pages;	/* # of pages in all non-dummy tables of
+									 * query */
+
+	double		tuple_fraction; /* tuple_fraction passed to query_planner */
+	double		limit_tuples;	/* limit_tuples passed to query_planner */
+
+	Index		qual_security_level;	/* minimum security_level for quals */
+	/* Note: qual_security_level is zero if there are no securityQuals */
+
+	InheritanceKind inhTargetKind;	/* indicates if the target relation is an
+									 * inheritance child or partition or a
+									 * partitioned table */
+	bool		hasJoinRTEs;	/* true if any RTEs are RTE_JOIN kind */
+	bool		hasLateralRTEs; /* true if any RTEs are marked LATERAL */
+	bool		hasHavingQual;	/* true if havingQual was non-null */
+	bool		hasPseudoConstantQuals; /* true if any RestrictInfo has
+										 * pseudoconstant = true */
+	bool		hasRecursion;	/* true if planning a recursive WITH item */
+
+	/* These fields are used only when hasRecursion is true: */
+	int			wt_param_id;	/* PARAM_EXEC ID for the work table */
+	struct Path *non_recursive_path;	/* a path for non-recursive term */
+
+	/* These fields are workspace for createplan.c */
+	Relids		curOuterRels;	/* outer rels above current node */
+	List	   *curOuterParams; /* not-yet-assigned NestLoopParams */
+
+	/* optional private data for join_search_hook, e.g., GEQO */
+	void	   *join_search_private;
+
+	/* Does this query modify any partition key columns? */
+	bool		partColsUpdated;
+};
+
+
+/*
+ * In places where it's known that simple_rte_array[] must have been prepared
+ * already, we just index into it to fetch RTEs.  In code that might be
+ * executed before or after entering query_planner(), use this macro.
+ */
+#define planner_rt_fetch(rti, root) \
+	((root)->simple_rte_array ? (root)->simple_rte_array[rti] : \
+	 rt_fetch(rti, (root)->parse->rtable))
+
+/*
+ * If multiple relations are partitioned the same way, all such partitions
+ * will have a pointer to the same PartitionScheme.  A list of PartitionScheme
+ * objects is attached to the PlannerInfo.  By design, the partition scheme
+ * incorporates only the general properties of the partition method (LIST vs.
+ * RANGE, number of partitioning columns and the type information for each)
+ * and not the specific bounds.
+ *
+ * We store the opclass-declared input data types instead of the partition key
+ * datatypes since the former rather than the latter are used to compare
+ * partition bounds. Since partition key data types and the opclass declared
+ * input data types are expected to be binary compatible (per ResolveOpClass),
+ * both of those should have same byval and length properties.
+ */
+typedef struct PartitionSchemeData
+{
+	char		strategy;		/* partition strategy */
+	int16		partnatts;		/* number of partition attributes */
+	Oid		   *partopfamily;	/* OIDs of operator families */
+	Oid		   *partopcintype;	/* OIDs of opclass declared input data types */
+	Oid		   *partcollation;	/* OIDs of partitioning collations */
+
+	/* Cached information about partition key data types. */
+	int16	   *parttyplen;
+	bool	   *parttypbyval;
+
+	/* Cached information about partition comparison functions. */
+	struct FmgrInfo *partsupfunc;
+}			PartitionSchemeData;
+
+typedef struct PartitionSchemeData *PartitionScheme;
+
+/*----------
+ * RelOptInfo
+ *		Per-relation information for planning/optimization
+ *
+ * For planning purposes, a "base rel" is either a plain relation (a table)
+ * or the output of a sub-SELECT or function that appears in the range table.
+ * In either case it is uniquely identified by an RT index.  A "joinrel"
+ * is the joining of two or more base rels.  A joinrel is identified by
+ * the set of RT indexes for its component baserels.  We create RelOptInfo
+ * nodes for each baserel and joinrel, and store them in the PlannerInfo's
+ * simple_rel_array and join_rel_list respectively.
+ *
+ * Note that there is only one joinrel for any given set of component
+ * baserels, no matter what order we assemble them in; so an unordered
+ * set is the right datatype to identify it with.
+ *
+ * We also have "other rels", which are like base rels in that they refer to
+ * single RT indexes; but they are not part of the join tree, and are given
+ * a different RelOptKind to identify them.
+ * Currently the only kind of otherrels are those made for member relations
+ * of an "append relation", that is an inheritance set or UNION ALL subquery.
+ * An append relation has a parent RTE that is a base rel, which represents
+ * the entire append relation.  The member RTEs are otherrels.  The parent
+ * is present in the query join tree but the members are not.  The member
+ * RTEs and otherrels are used to plan the scans of the individual tables or
+ * subqueries of the append set; then the parent baserel is given Append
+ * and/or MergeAppend paths comprising the best paths for the individual
+ * member rels.  (See comments for AppendRelInfo for more information.)
+ *
+ * At one time we also made otherrels to represent join RTEs, for use in
+ * handling join alias Vars.  Currently this is not needed because all join
+ * alias Vars are expanded to non-aliased form during preprocess_expression.
+ *
+ * We also have relations representing joins between child relations of
+ * different partitioned tables. These relations are not added to
+ * join_rel_level lists as they are not joined directly by the dynamic
+ * programming algorithm.
+ *
+ * There is also a RelOptKind for "upper" relations, which are RelOptInfos
+ * that describe post-scan/join processing steps, such as aggregation.
+ * Many of the fields in these RelOptInfos are meaningless, but their Path
+ * fields always hold Paths showing ways to do that processing step.
+ *
+ * Lastly, there is a RelOptKind for "dead" relations, which are base rels
+ * that we have proven we don't need to join after all.
+ *
+ * Parts of this data structure are specific to various scan and join
+ * mechanisms.  It didn't seem worth creating new node types for them.
+ *
+ *		relids - Set of base-relation identifiers; it is a base relation
+ *				if there is just one, a join relation if more than one
+ *		rows - estimated number of tuples in the relation after restriction
+ *			   clauses have been applied (ie, output rows of a plan for it)
+ *		consider_startup - true if there is any value in keeping plain paths for
+ *						   this rel on the basis of having cheap startup cost
+ *		consider_param_startup - the same for parameterized paths
+ *		reltarget - Default Path output tlist for this rel; normally contains
+ *					Var and PlaceHolderVar nodes for the values we need to
+ *					output from this relation.
+ *					List is in no particular order, but all rels of an
+ *					appendrel set must use corresponding orders.
+ *					NOTE: in an appendrel child relation, may contain
+ *					arbitrary expressions pulled up from a subquery!
+ *		pathlist - List of Path nodes, one for each potentially useful
+ *				   method of generating the relation
+ *		ppilist - ParamPathInfo nodes for parameterized Paths, if any
+ *		cheapest_startup_path - the pathlist member with lowest startup cost
+ *			(regardless of ordering) among the unparameterized paths;
+ *			or NULL if there is no unparameterized path
+ *		cheapest_total_path - the pathlist member with lowest total cost
+ *			(regardless of ordering) among the unparameterized paths;
+ *			or if there is no unparameterized path, the path with lowest
+ *			total cost among the paths with minimum parameterization
+ *		cheapest_unique_path - for caching cheapest path to produce unique
+ *			(no duplicates) output from relation; NULL if not yet requested
+ *		cheapest_parameterized_paths - best paths for their parameterizations;
+ *			always includes cheapest_total_path, even if that's unparameterized
+ *		direct_lateral_relids - rels this rel has direct LATERAL references to
+ *		lateral_relids - required outer rels for LATERAL, as a Relids set
+ *			(includes both direct and indirect lateral references)
+ *
+ * If the relation is a base relation it will have these fields set:
+ *
+ *		relid - RTE index (this is redundant with the relids field, but
+ *				is provided for convenience of access)
+ *		rtekind - copy of RTE's rtekind field
+ *		min_attr, max_attr - range of valid AttrNumbers for rel
+ *		attr_needed - array of bitmapsets indicating the highest joinrel
+ *				in which each attribute is needed; if bit 0 is set then
+ *				the attribute is needed as part of final targetlist
+ *		attr_widths - cache space for per-attribute width estimates;
+ *					  zero means not computed yet
+ *		lateral_vars - lateral cross-references of rel, if any (list of
+ *					   Vars and PlaceHolderVars)
+ *		lateral_referencers - relids of rels that reference this one laterally
+ *				(includes both direct and indirect lateral references)
+ *		indexlist - list of IndexOptInfo nodes for relation's indexes
+ *					(always NIL if it's not a table)
+ *		pages - number of disk pages in relation (zero if not a table)
+ *		tuples - number of tuples in relation (not considering restrictions)
+ *		allvisfrac - fraction of disk pages that are marked all-visible
+ *		eclass_indexes - EquivalenceClasses that mention this rel (filled
+ *						 only after EC merging is complete)
+ *		subroot - PlannerInfo for subquery (NULL if it's not a subquery)
+ *		subplan_params - list of PlannerParamItems to be passed to subquery
+ *
+ *		Note: for a subquery, tuples and subroot are not set immediately
+ *		upon creation of the RelOptInfo object; they are filled in when
+ *		set_subquery_pathlist processes the object.
+ *
+ *		For otherrels that are appendrel members, these fields are filled
+ *		in just as for a baserel, except we don't bother with lateral_vars.
+ *
+ * If the relation is either a foreign table or a join of foreign tables that
+ * all belong to the same foreign server and are assigned to the same user to
+ * check access permissions as (cf checkAsUser), these fields will be set:
+ *
+ *		serverid - OID of foreign server, if foreign table (else InvalidOid)
+ *		userid - OID of user to check access as (InvalidOid means current user)
+ *		useridiscurrent - we've assumed that userid equals current user
+ *		fdwroutine - function hooks for FDW, if foreign table (else NULL)
+ *		fdw_private - private state for FDW, if foreign table (else NULL)
+ *
+ * Two fields are used to cache knowledge acquired during the join search
+ * about whether this rel is provably unique when being joined to given other
+ * relation(s), ie, it can have at most one row matching any given row from
+ * that join relation.  Currently we only attempt such proofs, and thus only
+ * populate these fields, for base rels; but someday they might be used for
+ * join rels too:
+ *
+ *		unique_for_rels - list of Relid sets, each one being a set of other
+ *					rels for which this one has been proven unique
+ *		non_unique_for_rels - list of Relid sets, each one being a set of
+ *					other rels for which we have tried and failed to prove
+ *					this one unique
+ *
+ * The presence of the following fields depends on the restrictions
+ * and joins that the relation participates in:
+ *
+ *		baserestrictinfo - List of RestrictInfo nodes, containing info about
+ *					each non-join qualification clause in which this relation
+ *					participates (only used for base rels)
+ *		baserestrictcost - Estimated cost of evaluating the baserestrictinfo
+ *					clauses at a single tuple (only used for base rels)
+ *		baserestrict_min_security - Smallest security_level found among
+ *					clauses in baserestrictinfo
+ *		joininfo  - List of RestrictInfo nodes, containing info about each
+ *					join clause in which this relation participates (but
+ *					note this excludes clauses that might be derivable from
+ *					EquivalenceClasses)
+ *		has_eclass_joins - flag that EquivalenceClass joins are possible
+ *
+ * Note: Keeping a restrictinfo list in the RelOptInfo is useful only for
+ * base rels, because for a join rel the set of clauses that are treated as
+ * restrict clauses varies depending on which sub-relations we choose to join.
+ * (For example, in a 3-base-rel join, a clause relating rels 1 and 2 must be
+ * treated as a restrictclause if we join {1} and {2 3} to make {1 2 3}; but
+ * if we join {1 2} and {3} then that clause will be a restrictclause in {1 2}
+ * and should not be processed again at the level of {1 2 3}.)	Therefore,
+ * the restrictinfo list in the join case appears in individual JoinPaths
+ * (field joinrestrictinfo), not in the parent relation.  But it's OK for
+ * the RelOptInfo to store the joininfo list, because that is the same
+ * for a given rel no matter how we form it.
+ *
+ * We store baserestrictcost in the RelOptInfo (for base relations) because
+ * we know we will need it at least once (to price the sequential scan)
+ * and may need it multiple times to price index scans.
+ *
+ * A join relation is considered to be partitioned if it is formed from a
+ * join of two relations that are partitioned, have matching partitioning
+ * schemes, and are joined on an equijoin of the partitioning columns.
+ * Under those conditions we can consider the join relation to be partitioned
+ * by either relation's partitioning keys, though some care is needed if
+ * either relation can be forced to null by outer-joining.  For example, an
+ * outer join like (A LEFT JOIN B ON A.a = B.b) may produce rows with B.b
+ * NULL.  These rows may not fit the partitioning conditions imposed on B.
+ * Hence, strictly speaking, the join is not partitioned by B.b and thus
+ * partition keys of an outer join should include partition key expressions
+ * from the non-nullable side only.  However, if a subsequent join uses
+ * strict comparison operators (and all commonly-used equijoin operators are
+ * strict), the presence of nulls doesn't cause a problem: such rows couldn't
+ * match anything on the other side and thus they don't create a need to do
+ * any cross-partition sub-joins.  Hence we can treat such values as still
+ * partitioning the join output for the purpose of additional partitionwise
+ * joining, so long as a strict join operator is used by the next join.
+ *
+ * If the relation is partitioned, these fields will be set:
+ *
+ *		part_scheme - Partitioning scheme of the relation
+ *		nparts - Number of partitions
+ *		boundinfo - Partition bounds
+ *		partbounds_merged - true if partition bounds are merged ones
+ *		partition_qual - Partition constraint if not the root
+ *		part_rels - RelOptInfos for each partition
+ *		all_partrels - Relids set of all partition relids
+ *		partexprs, nullable_partexprs - Partition key expressions
+ *		partitioned_child_rels - RT indexes of unpruned partitions of
+ *								 this relation that are partitioned tables
+ *								 themselves, in hierarchical order
+ *
+ * The partexprs and nullable_partexprs arrays each contain
+ * part_scheme->partnatts elements.  Each of the elements is a list of
+ * partition key expressions.  For partitioned base relations, there is one
+ * expression in each partexprs element, and nullable_partexprs is empty.
+ * For partitioned join relations, each base relation within the join
+ * contributes one partition key expression per partitioning column;
+ * that expression goes in the partexprs[i] list if the base relation
+ * is not nullable by this join or any lower outer join, or in the
+ * nullable_partexprs[i] list if the base relation is nullable.
+ * Furthermore, FULL JOINs add extra nullable_partexprs expressions
+ * corresponding to COALESCE expressions of the left and right join columns,
+ * to simplify matching join clauses to those lists.
+ *----------
+ */
+typedef enum RelOptKind
+{
+	RELOPT_BASEREL,
+	RELOPT_JOINREL,
+	RELOPT_OTHER_MEMBER_REL,
+	RELOPT_OTHER_JOINREL,
+	RELOPT_UPPER_REL,
+	RELOPT_OTHER_UPPER_REL,
+	RELOPT_DEADREL
+} RelOptKind;
+
+/*
+ * Is the given relation a simple relation i.e a base or "other" member
+ * relation?
+ */
+#define IS_SIMPLE_REL(rel) \
+	((rel)->reloptkind == RELOPT_BASEREL || \
+	 (rel)->reloptkind == RELOPT_OTHER_MEMBER_REL)
+
+/* Is the given relation a join relation? */
+#define IS_JOIN_REL(rel)	\
+	((rel)->reloptkind == RELOPT_JOINREL || \
+	 (rel)->reloptkind == RELOPT_OTHER_JOINREL)
+
+/* Is the given relation an upper relation? */
+#define IS_UPPER_REL(rel)	\
+	((rel)->reloptkind == RELOPT_UPPER_REL || \
+	 (rel)->reloptkind == RELOPT_OTHER_UPPER_REL)
+
+/* Is the given relation an "other" relation? */
+#define IS_OTHER_REL(rel) \
+	((rel)->reloptkind == RELOPT_OTHER_MEMBER_REL || \
+	 (rel)->reloptkind == RELOPT_OTHER_JOINREL || \
+	 (rel)->reloptkind == RELOPT_OTHER_UPPER_REL)
+
+typedef struct RelOptInfo
+{
+	NodeTag		type;
+
+	RelOptKind	reloptkind;
+
+	/* all relations included in this RelOptInfo */
+	Relids		relids;			/* set of base relids (rangetable indexes) */
+
+	/* size estimates generated by planner */
+	double		rows;			/* estimated number of result tuples */
+
+	/* per-relation planner control flags */
+	bool		consider_startup;	/* keep cheap-startup-cost paths? */
+	bool		consider_param_startup; /* ditto, for parameterized paths? */
+	bool		consider_parallel;	/* consider parallel paths? */
+
+	/* default result targetlist for Paths scanning this relation */
+	struct PathTarget *reltarget;	/* list of Vars/Exprs, cost, width */
+
+	/* materialization information */
+	List	   *pathlist;		/* Path structures */
+	List	   *ppilist;		/* ParamPathInfos used in pathlist */
+	List	   *partial_pathlist;	/* partial Paths */
+	struct Path *cheapest_startup_path;
+	struct Path *cheapest_total_path;
+	struct Path *cheapest_unique_path;
+	List	   *cheapest_parameterized_paths;
+
+	/* parameterization information needed for both base rels and join rels */
+	/* (see also lateral_vars and lateral_referencers) */
+	Relids		direct_lateral_relids;	/* rels directly laterally referenced */
+	Relids		lateral_relids; /* minimum parameterization of rel */
+
+	/* information about a base rel (not set for join rels!) */
+	Index		relid;
+	Oid			reltablespace;	/* containing tablespace */
+	RTEKind		rtekind;		/* RELATION, SUBQUERY, FUNCTION, etc */
+	AttrNumber	min_attr;		/* smallest attrno of rel (often <0) */
+	AttrNumber	max_attr;		/* largest attrno of rel */
+	Relids	   *attr_needed;	/* array indexed [min_attr .. max_attr] */
+	int32	   *attr_widths;	/* array indexed [min_attr .. max_attr] */
+	List	   *lateral_vars;	/* LATERAL Vars and PHVs referenced by rel */
+	Relids		lateral_referencers;	/* rels that reference me laterally */
+	List	   *indexlist;		/* list of IndexOptInfo */
+	List	   *statlist;		/* list of StatisticExtInfo */
+	BlockNumber pages;			/* size estimates derived from pg_class */
+	double		tuples;
+	double		allvisfrac;
+	Bitmapset  *eclass_indexes; /* Indexes in PlannerInfo's eq_classes list of
+								 * ECs that mention this rel */
+	PlannerInfo *subroot;		/* if subquery */
+	List	   *subplan_params; /* if subquery */
+	int			rel_parallel_workers;	/* wanted number of parallel workers */
+
+	/* Information about foreign tables and foreign joins */
+	Oid			serverid;		/* identifies server for the table or join */
+	Oid			userid;			/* identifies user to check access as */
+	bool		useridiscurrent;	/* join is only valid for current user */
+	/* use "struct FdwRoutine" to avoid including fdwapi.h here */
+	struct FdwRoutine *fdwroutine;
+	void	   *fdw_private;
+
+	/* cache space for remembering if we have proven this relation unique */
+	List	   *unique_for_rels;	/* known unique for these other relid
+									 * set(s) */
+	List	   *non_unique_for_rels;	/* known not unique for these set(s) */
+
+	/* used by various scans and joins: */
+	List	   *baserestrictinfo;	/* RestrictInfo structures (if base rel) */
+	QualCost	baserestrictcost;	/* cost of evaluating the above */
+	Index		baserestrict_min_security;	/* min security_level found in
+											 * baserestrictinfo */
+	List	   *joininfo;		/* RestrictInfo structures for join clauses
+								 * involving this rel */
+	bool		has_eclass_joins;	/* T means joininfo is incomplete */
+
+	/* used by partitionwise joins: */
+	bool		consider_partitionwise_join;	/* consider partitionwise join
+												 * paths? (if partitioned rel) */
+	Relids		top_parent_relids;	/* Relids of topmost parents (if "other"
+									 * rel) */
+
+	/* used for partitioned relations: */
+	PartitionScheme part_scheme;	/* Partitioning scheme */
+	int			nparts;			/* Number of partitions; -1 if not yet set; in
+								 * case of a join relation 0 means it's
+								 * considered unpartitioned */
+	struct PartitionBoundInfoData *boundinfo;	/* Partition bounds */
+	bool		partbounds_merged;	/* True if partition bounds were created
+									 * by partition_bounds_merge() */
+	List	   *partition_qual; /* Partition constraint, if not the root */
+	struct RelOptInfo **part_rels;	/* Array of RelOptInfos of partitions,
+									 * stored in the same order as bounds */
+	Relids		all_partrels;	/* Relids set of all partition relids */
+	List	  **partexprs;		/* Non-nullable partition key expressions */
+	List	  **nullable_partexprs; /* Nullable partition key expressions */
+	List	   *partitioned_child_rels; /* List of RT indexes */
+} RelOptInfo;
+
+/*
+ * Is given relation partitioned?
+ *
+ * It's not enough to test whether rel->part_scheme is set, because it might
+ * be that the basic partitioning properties of the input relations matched
+ * but the partition bounds did not.  Also, if we are able to prove a rel
+ * dummy (empty), we should henceforth treat it as unpartitioned.
+ */
+#define IS_PARTITIONED_REL(rel) \
+	((rel)->part_scheme && (rel)->boundinfo && (rel)->nparts > 0 && \
+	 (rel)->part_rels && !IS_DUMMY_REL(rel))
+
+/*
+ * Convenience macro to make sure that a partitioned relation has all the
+ * required members set.
+ */
+#define REL_HAS_ALL_PART_PROPS(rel)	\
+	((rel)->part_scheme && (rel)->boundinfo && (rel)->nparts > 0 && \
+	 (rel)->part_rels && (rel)->partexprs && (rel)->nullable_partexprs)
+
+/*
+ * IndexOptInfo
+ *		Per-index information for planning/optimization
+ *
+ *		indexkeys[], indexcollations[] each have ncolumns entries.
+ *		opfamily[], and opcintype[]	each have nkeycolumns entries. They do
+ *		not contain any information about included attributes.
+ *
+ *		sortopfamily[], reverse_sort[], and nulls_first[] have
+ *		nkeycolumns entries, if the index is ordered; but if it is unordered,
+ *		those pointers are NULL.
+ *
+ *		Zeroes in the indexkeys[] array indicate index columns that are
+ *		expressions; there is one element in indexprs for each such column.
+ *
+ *		For an ordered index, reverse_sort[] and nulls_first[] describe the
+ *		sort ordering of a forward indexscan; we can also consider a backward
+ *		indexscan, which will generate the reverse ordering.
+ *
+ *		The indexprs and indpred expressions have been run through
+ *		prepqual.c and eval_const_expressions() for ease of matching to
+ *		WHERE clauses. indpred is in implicit-AND form.
+ *
+ *		indextlist is a TargetEntry list representing the index columns.
+ *		It provides an equivalent base-relation Var for each simple column,
+ *		and links to the matching indexprs element for each expression column.
+ *
+ *		While most of these fields are filled when the IndexOptInfo is created
+ *		(by plancat.c), indrestrictinfo and predOK are set later, in
+ *		check_index_predicates().
+ */
+#ifndef HAVE_INDEXOPTINFO_TYPEDEF
+typedef struct IndexOptInfo IndexOptInfo;
+#define HAVE_INDEXOPTINFO_TYPEDEF 1
+#endif
+
+struct IndexOptInfo
+{
+	NodeTag		type;
+
+	Oid			indexoid;		/* OID of the index relation */
+	Oid			reltablespace;	/* tablespace of index (not table) */
+	RelOptInfo *rel;			/* back-link to index's table */
+
+	/* index-size statistics (from pg_class and elsewhere) */
+	BlockNumber pages;			/* number of disk pages in index */
+	double		tuples;			/* number of index tuples in index */
+	int			tree_height;	/* index tree height, or -1 if unknown */
+
+	/* index descriptor information */
+	int			ncolumns;		/* number of columns in index */
+	int			nkeycolumns;	/* number of key columns in index */
+	int		   *indexkeys;		/* column numbers of index's attributes both
+								 * key and included columns, or 0 */
+	Oid		   *indexcollations;	/* OIDs of collations of index columns */
+	Oid		   *opfamily;		/* OIDs of operator families for columns */
+	Oid		   *opcintype;		/* OIDs of opclass declared input data types */
+	Oid		   *sortopfamily;	/* OIDs of btree opfamilies, if orderable */
+	bool	   *reverse_sort;	/* is sort order descending? */
+	bool	   *nulls_first;	/* do NULLs come first in the sort order? */
+	bytea	  **opclassoptions; /* opclass-specific options for columns */
+	bool	   *canreturn;		/* which index cols can be returned in an
+								 * index-only scan? */
+	Oid			relam;			/* OID of the access method (in pg_am) */
+
+	List	   *indexprs;		/* expressions for non-simple index columns */
+	List	   *indpred;		/* predicate if a partial index, else NIL */
+
+	List	   *indextlist;		/* targetlist representing index columns */
+
+	List	   *indrestrictinfo;	/* parent relation's baserestrictinfo
+									 * list, less any conditions implied by
+									 * the index's predicate (unless it's a
+									 * target rel, see comments in
+									 * check_index_predicates()) */
+
+	bool		predOK;			/* true if index predicate matches query */
+	bool		unique;			/* true if a unique index */
+	bool		immediate;		/* is uniqueness enforced immediately? */
+	bool		hypothetical;	/* true if index doesn't really exist */
+
+	/* Remaining fields are copied from the index AM's API struct: */
+	bool		amcanorderbyop; /* does AM support order by operator result? */
+	bool		amoptionalkey;	/* can query omit key for the first column? */
+	bool		amsearcharray;	/* can AM handle ScalarArrayOpExpr quals? */
+	bool		amsearchnulls;	/* can AM search for NULL/NOT NULL entries? */
+	bool		amhasgettuple;	/* does AM have amgettuple interface? */
+	bool		amhasgetbitmap; /* does AM have amgetbitmap interface? */
+	bool		amcanparallel;	/* does AM support parallel scan? */
+	bool		amcanmarkpos;	/* does AM support mark/restore? */
+	/* Rather than include amapi.h here, we declare amcostestimate like this */
+	void		(*amcostestimate) ();	/* AM's cost estimator */
+};
+
+/*
+ * ForeignKeyOptInfo
+ *		Per-foreign-key information for planning/optimization
+ *
+ * The per-FK-column arrays can be fixed-size because we allow at most
+ * INDEX_MAX_KEYS columns in a foreign key constraint.  Each array has
+ * nkeys valid entries.
+ */
+typedef struct ForeignKeyOptInfo
+{
+	NodeTag		type;
+
+	/* Basic data about the foreign key (fetched from catalogs): */
+	Index		con_relid;		/* RT index of the referencing table */
+	Index		ref_relid;		/* RT index of the referenced table */
+	int			nkeys;			/* number of columns in the foreign key */
+	AttrNumber	conkey[INDEX_MAX_KEYS]; /* cols in referencing table */
+	AttrNumber	confkey[INDEX_MAX_KEYS];	/* cols in referenced table */
+	Oid			conpfeqop[INDEX_MAX_KEYS];	/* PK = FK operator OIDs */
+
+	/* Derived info about whether FK's equality conditions match the query: */
+	int			nmatched_ec;	/* # of FK cols matched by ECs */
+	int			nmatched_rcols; /* # of FK cols matched by non-EC rinfos */
+	int			nmatched_ri;	/* total # of non-EC rinfos matched to FK */
+	/* Pointer to eclass matching each column's condition, if there is one */
+	struct EquivalenceClass *eclass[INDEX_MAX_KEYS];
+	/* List of non-EC RestrictInfos matching each column's condition */
+	List	   *rinfos[INDEX_MAX_KEYS];
+} ForeignKeyOptInfo;
+
+/*
+ * StatisticExtInfo
+ *		Information about extended statistics for planning/optimization
+ *
+ * Each pg_statistic_ext row is represented by one or more nodes of this
+ * type, or even zero if ANALYZE has not computed them.
+ */
+typedef struct StatisticExtInfo
+{
+	NodeTag		type;
+
+	Oid			statOid;		/* OID of the statistics row */
+	RelOptInfo *rel;			/* back-link to statistic's table */
+	char		kind;			/* statistics kind of this entry */
+	Bitmapset  *keys;			/* attnums of the columns covered */
+} StatisticExtInfo;
+
+/*
+ * EquivalenceClasses
+ *
+ * Whenever we can determine that a mergejoinable equality clause A = B is
+ * not delayed by any outer join, we create an EquivalenceClass containing
+ * the expressions A and B to record this knowledge.  If we later find another
+ * equivalence B = C, we add C to the existing EquivalenceClass; this may
+ * require merging two existing EquivalenceClasses.  At the end of the qual
+ * distribution process, we have sets of values that are known all transitively
+ * equal to each other, where "equal" is according to the rules of the btree
+ * operator family(s) shown in ec_opfamilies, as well as the collation shown
+ * by ec_collation.  (We restrict an EC to contain only equalities whose
+ * operators belong to the same set of opfamilies.  This could probably be
+ * relaxed, but for now it's not worth the trouble, since nearly all equality
+ * operators belong to only one btree opclass anyway.  Similarly, we suppose
+ * that all or none of the input datatypes are collatable, so that a single
+ * collation value is sufficient.)
+ *
+ * We also use EquivalenceClasses as the base structure for PathKeys, letting
+ * us represent knowledge about different sort orderings being equivalent.
+ * Since every PathKey must reference an EquivalenceClass, we will end up
+ * with single-member EquivalenceClasses whenever a sort key expression has
+ * not been equivalenced to anything else.  It is also possible that such an
+ * EquivalenceClass will contain a volatile expression ("ORDER BY random()"),
+ * which is a case that can't arise otherwise since clauses containing
+ * volatile functions are never considered mergejoinable.  We mark such
+ * EquivalenceClasses specially to prevent them from being merged with
+ * ordinary EquivalenceClasses.  Also, for volatile expressions we have
+ * to be careful to match the EquivalenceClass to the correct targetlist
+ * entry: consider SELECT random() AS a, random() AS b ... ORDER BY b,a.
+ * So we record the SortGroupRef of the originating sort clause.
+ *
+ * We allow equality clauses appearing below the nullable side of an outer join
+ * to form EquivalenceClasses, but these have a slightly different meaning:
+ * the included values might be all NULL rather than all the same non-null
+ * values.  See src/backend/optimizer/README for more on that point.
+ *
+ * NB: if ec_merged isn't NULL, this class has been merged into another, and
+ * should be ignored in favor of using the pointed-to class.
+ */
+typedef struct EquivalenceClass
+{
+	NodeTag		type;
+
+	List	   *ec_opfamilies;	/* btree operator family OIDs */
+	Oid			ec_collation;	/* collation, if datatypes are collatable */
+	List	   *ec_members;		/* list of EquivalenceMembers */
+	List	   *ec_sources;		/* list of generating RestrictInfos */
+	List	   *ec_derives;		/* list of derived RestrictInfos */
+	Relids		ec_relids;		/* all relids appearing in ec_members, except
+								 * for child members (see below) */
+	bool		ec_has_const;	/* any pseudoconstants in ec_members? */
+	bool		ec_has_volatile;	/* the (sole) member is a volatile expr */
+	bool		ec_below_outer_join;	/* equivalence applies below an OJ */
+	bool		ec_broken;		/* failed to generate needed clauses? */
+	Index		ec_sortref;		/* originating sortclause label, or 0 */
+	Index		ec_min_security;	/* minimum security_level in ec_sources */
+	Index		ec_max_security;	/* maximum security_level in ec_sources */
+	struct EquivalenceClass *ec_merged; /* set if merged into another EC */
+} EquivalenceClass;
+
+/*
+ * If an EC contains a const and isn't below-outer-join, any PathKey depending
+ * on it must be redundant, since there's only one possible value of the key.
+ */
+#define EC_MUST_BE_REDUNDANT(eclass)  \
+	((eclass)->ec_has_const && !(eclass)->ec_below_outer_join)
+
+/*
+ * EquivalenceMember - one member expression of an EquivalenceClass
+ *
+ * em_is_child signifies that this element was built by transposing a member
+ * for an appendrel parent relation to represent the corresponding expression
+ * for an appendrel child.  These members are used for determining the
+ * pathkeys of scans on the child relation and for explicitly sorting the
+ * child when necessary to build a MergeAppend path for the whole appendrel
+ * tree.  An em_is_child member has no impact on the properties of the EC as a
+ * whole; in particular the EC's ec_relids field does NOT include the child
+ * relation.  An em_is_child member should never be marked em_is_const nor
+ * cause ec_has_const or ec_has_volatile to be set, either.  Thus, em_is_child
+ * members are not really full-fledged members of the EC, but just reflections
+ * or doppelgangers of real members.  Most operations on EquivalenceClasses
+ * should ignore em_is_child members, and those that don't should test
+ * em_relids to make sure they only consider relevant members.
+ *
+ * em_datatype is usually the same as exprType(em_expr), but can be
+ * different when dealing with a binary-compatible opfamily; in particular
+ * anyarray_ops would never work without this.  Use em_datatype when
+ * looking up a specific btree operator to work with this expression.
+ */
+typedef struct EquivalenceMember
+{
+	NodeTag		type;
+
+	Expr	   *em_expr;		/* the expression represented */
+	Relids		em_relids;		/* all relids appearing in em_expr */
+	Relids		em_nullable_relids; /* nullable by lower outer joins */
+	bool		em_is_const;	/* expression is pseudoconstant? */
+	bool		em_is_child;	/* derived version for a child relation? */
+	Oid			em_datatype;	/* the "nominal type" used by the opfamily */
+} EquivalenceMember;
+
+/*
+ * PathKeys
+ *
+ * The sort ordering of a path is represented by a list of PathKey nodes.
+ * An empty list implies no known ordering.  Otherwise the first item
+ * represents the primary sort key, the second the first secondary sort key,
+ * etc.  The value being sorted is represented by linking to an
+ * EquivalenceClass containing that value and including pk_opfamily among its
+ * ec_opfamilies.  The EquivalenceClass tells which collation to use, too.
+ * This is a convenient method because it makes it trivial to detect
+ * equivalent and closely-related orderings. (See optimizer/README for more
+ * information.)
+ *
+ * Note: pk_strategy is either BTLessStrategyNumber (for ASC) or
+ * BTGreaterStrategyNumber (for DESC).  We assume that all ordering-capable
+ * index types will use btree-compatible strategy numbers.
+ */
+typedef struct PathKey
+{
+	NodeTag		type;
+
+	EquivalenceClass *pk_eclass;	/* the value that is ordered */
+	Oid			pk_opfamily;	/* btree opfamily defining the ordering */
+	int			pk_strategy;	/* sort direction (ASC or DESC) */
+	bool		pk_nulls_first; /* do NULLs come before normal values? */
+} PathKey;
+
+
+/*
+ * PathTarget
+ *
+ * This struct contains what we need to know during planning about the
+ * targetlist (output columns) that a Path will compute.  Each RelOptInfo
+ * includes a default PathTarget, which its individual Paths may simply
+ * reference.  However, in some cases a Path may compute outputs different
+ * from other Paths, and in that case we make a custom PathTarget for it.
+ * For example, an indexscan might return index expressions that would
+ * otherwise need to be explicitly calculated.  (Note also that "upper"
+ * relations generally don't have useful default PathTargets.)
+ *
+ * exprs contains bare expressions; they do not have TargetEntry nodes on top,
+ * though those will appear in finished Plans.
+ *
+ * sortgrouprefs[] is an array of the same length as exprs, containing the
+ * corresponding sort/group refnos, or zeroes for expressions not referenced
+ * by sort/group clauses.  If sortgrouprefs is NULL (which it generally is in
+ * RelOptInfo.reltarget targets; only upper-level Paths contain this info),
+ * we have not identified sort/group columns in this tlist.  This allows us to
+ * deal with sort/group refnos when needed with less expense than including
+ * TargetEntry nodes in the exprs list.
+ */
+typedef struct PathTarget
+{
+	NodeTag		type;
+	List	   *exprs;			/* list of expressions to be computed */
+	Index	   *sortgrouprefs;	/* corresponding sort/group refnos, or 0 */
+	QualCost	cost;			/* cost of evaluating the expressions */
+	int			width;			/* estimated avg width of result tuples */
+} PathTarget;
+
+/* Convenience macro to get a sort/group refno from a PathTarget */
+#define get_pathtarget_sortgroupref(target, colno) \
+	((target)->sortgrouprefs ? (target)->sortgrouprefs[colno] : (Index) 0)
+
+
+/*
+ * ParamPathInfo
+ *
+ * All parameterized paths for a given relation with given required outer rels
+ * link to a single ParamPathInfo, which stores common information such as
+ * the estimated rowcount for this parameterization.  We do this partly to
+ * avoid recalculations, but mostly to ensure that the estimated rowcount
+ * is in fact the same for every such path.
+ *
+ * Note: ppi_clauses is only used in ParamPathInfos for base relation paths;
+ * in join cases it's NIL because the set of relevant clauses varies depending
+ * on how the join is formed.  The relevant clauses will appear in each
+ * parameterized join path's joinrestrictinfo list, instead.
+ */
+typedef struct ParamPathInfo
+{
+	NodeTag		type;
+
+	Relids		ppi_req_outer;	/* rels supplying parameters used by path */
+	double		ppi_rows;		/* estimated number of result tuples */
+	List	   *ppi_clauses;	/* join clauses available from outer rels */
+} ParamPathInfo;
+
+
+/*
+ * Type "Path" is used as-is for sequential-scan paths, as well as some other
+ * simple plan types that we don't need any extra information in the path for.
+ * For other path types it is the first component of a larger struct.
+ *
+ * "pathtype" is the NodeTag of the Plan node we could build from this Path.
+ * It is partially redundant with the Path's NodeTag, but allows us to use
+ * the same Path type for multiple Plan types when there is no need to
+ * distinguish the Plan type during path processing.
+ *
+ * "parent" identifies the relation this Path scans, and "pathtarget"
+ * describes the precise set of output columns the Path would compute.
+ * In simple cases all Paths for a given rel share the same targetlist,
+ * which we represent by having path->pathtarget equal to parent->reltarget.
+ *
+ * "param_info", if not NULL, links to a ParamPathInfo that identifies outer
+ * relation(s) that provide parameter values to each scan of this path.
+ * That means this path can only be joined to those rels by means of nestloop
+ * joins with this path on the inside.  Also note that a parameterized path
+ * is responsible for testing all "movable" joinclauses involving this rel
+ * and the specified outer rel(s).
+ *
+ * "rows" is the same as parent->rows in simple paths, but in parameterized
+ * paths and UniquePaths it can be less than parent->rows, reflecting the
+ * fact that we've filtered by extra join conditions or removed duplicates.
+ *
+ * "pathkeys" is a List of PathKey nodes (see above), describing the sort
+ * ordering of the path's output rows.
+ */
+typedef struct Path
+{
+	NodeTag		type;
+
+	NodeTag		pathtype;		/* tag identifying scan/join method */
+
+	RelOptInfo *parent;			/* the relation this path can build */
+	PathTarget *pathtarget;		/* list of Vars/Exprs, cost, width */
+
+	ParamPathInfo *param_info;	/* parameterization info, or NULL if none */
+
+	bool		parallel_aware; /* engage parallel-aware logic? */
+	bool		parallel_safe;	/* OK to use as part of parallel plan? */
+	int			parallel_workers;	/* desired # of workers; 0 = not parallel */
+
+	/* estimated size/costs for path (see costsize.c for more info) */
+	double		rows;			/* estimated number of result tuples */
+	Cost		startup_cost;	/* cost expended before fetching any tuples */
+	Cost		total_cost;		/* total cost (assuming all tuples fetched) */
+
+	List	   *pathkeys;		/* sort ordering of path's output */
+	/* pathkeys is a List of PathKey nodes; see above */
+} Path;
+
+/* Macro for extracting a path's parameterization relids; beware double eval */
+#define PATH_REQ_OUTER(path)  \
+	((path)->param_info ? (path)->param_info->ppi_req_outer : (Relids) NULL)
+
+/*----------
+ * IndexPath represents an index scan over a single index.
+ *
+ * This struct is used for both regular indexscans and index-only scans;
+ * path.pathtype is T_IndexScan or T_IndexOnlyScan to show which is meant.
+ *
+ * 'indexinfo' is the index to be scanned.
+ *
+ * 'indexclauses' is a list of IndexClause nodes, each representing one
+ * index-checkable restriction, with implicit AND semantics across the list.
+ * An empty list implies a full index scan.
+ *
+ * 'indexorderbys', if not NIL, is a list of ORDER BY expressions that have
+ * been found to be usable as ordering operators for an amcanorderbyop index.
+ * The list must match the path's pathkeys, ie, one expression per pathkey
+ * in the same order.  These are not RestrictInfos, just bare expressions,
+ * since they generally won't yield booleans.  It's guaranteed that each
+ * expression has the index key on the left side of the operator.
+ *
+ * 'indexorderbycols' is an integer list of index column numbers (zero-based)
+ * of the same length as 'indexorderbys', showing which index column each
+ * ORDER BY expression is meant to be used with.  (There is no restriction
+ * on which index column each ORDER BY can be used with.)
+ *
+ * 'indexscandir' is one of:
+ *		ForwardScanDirection: forward scan of an ordered index
+ *		BackwardScanDirection: backward scan of an ordered index
+ *		NoMovementScanDirection: scan of an unordered index, or don't care
+ * (The executor doesn't care whether it gets ForwardScanDirection or
+ * NoMovementScanDirection for an indexscan, but the planner wants to
+ * distinguish ordered from unordered indexes for building pathkeys.)
+ *
+ * 'indextotalcost' and 'indexselectivity' are saved in the IndexPath so that
+ * we need not recompute them when considering using the same index in a
+ * bitmap index/heap scan (see BitmapHeapPath).  The costs of the IndexPath
+ * itself represent the costs of an IndexScan or IndexOnlyScan plan type.
+ *----------
+ */
+typedef struct IndexPath
+{
+	Path		path;
+	IndexOptInfo *indexinfo;
+	List	   *indexclauses;
+	List	   *indexorderbys;
+	List	   *indexorderbycols;
+	ScanDirection indexscandir;
+	Cost		indextotalcost;
+	Selectivity indexselectivity;
+} IndexPath;
+
+/*
+ * Each IndexClause references a RestrictInfo node from the query's WHERE
+ * or JOIN conditions, and shows how that restriction can be applied to
+ * the particular index.  We support both indexclauses that are directly
+ * usable by the index machinery, which are typically of the form
+ * "indexcol OP pseudoconstant", and those from which an indexable qual
+ * can be derived.  The simplest such transformation is that a clause
+ * of the form "pseudoconstant OP indexcol" can be commuted to produce an
+ * indexable qual (the index machinery expects the indexcol to be on the
+ * left always).  Another example is that we might be able to extract an
+ * indexable range condition from a LIKE condition, as in "x LIKE 'foo%bar'"
+ * giving rise to "x >= 'foo' AND x < 'fop'".  Derivation of such lossy
+ * conditions is done by a planner support function attached to the
+ * indexclause's top-level function or operator.
+ *
+ * indexquals is a list of RestrictInfos for the directly-usable index
+ * conditions associated with this IndexClause.  In the simplest case
+ * it's a one-element list whose member is iclause->rinfo.  Otherwise,
+ * it contains one or more directly-usable indexqual conditions extracted
+ * from the given clause.  The 'lossy' flag indicates whether the
+ * indexquals are semantically equivalent to the original clause, or
+ * represent a weaker condition.
+ *
+ * Normally, indexcol is the index of the single index column the clause
+ * works on, and indexcols is NIL.  But if the clause is a RowCompareExpr,
+ * indexcol is the index of the leading column, and indexcols is a list of
+ * all the affected columns.  (Note that indexcols matches up with the
+ * columns of the actual indexable RowCompareExpr in indexquals, which
+ * might be different from the original in rinfo.)
+ *
+ * An IndexPath's IndexClause list is required to be ordered by index
+ * column, i.e. the indexcol values must form a nondecreasing sequence.
+ * (The order of multiple clauses for the same index column is unspecified.)
+ */
+typedef struct IndexClause
+{
+	NodeTag		type;
+	struct RestrictInfo *rinfo; /* original restriction or join clause */
+	List	   *indexquals;		/* indexqual(s) derived from it */
+	bool		lossy;			/* are indexquals a lossy version of clause? */
+	AttrNumber	indexcol;		/* index column the clause uses (zero-based) */
+	List	   *indexcols;		/* multiple index columns, if RowCompare */
+} IndexClause;
+
+/*
+ * BitmapHeapPath represents one or more indexscans that generate TID bitmaps
+ * instead of directly accessing the heap, followed by AND/OR combinations
+ * to produce a single bitmap, followed by a heap scan that uses the bitmap.
+ * Note that the output is always considered unordered, since it will come
+ * out in physical heap order no matter what the underlying indexes did.
+ *
+ * The individual indexscans are represented by IndexPath nodes, and any
+ * logic on top of them is represented by a tree of BitmapAndPath and
+ * BitmapOrPath nodes.  Notice that we can use the same IndexPath node both
+ * to represent a regular (or index-only) index scan plan, and as the child
+ * of a BitmapHeapPath that represents scanning the same index using a
+ * BitmapIndexScan.  The startup_cost and total_cost figures of an IndexPath
+ * always represent the costs to use it as a regular (or index-only)
+ * IndexScan.  The costs of a BitmapIndexScan can be computed using the
+ * IndexPath's indextotalcost and indexselectivity.
+ */
+typedef struct BitmapHeapPath
+{
+	Path		path;
+	Path	   *bitmapqual;		/* IndexPath, BitmapAndPath, BitmapOrPath */
+} BitmapHeapPath;
+
+/*
+ * BitmapAndPath represents a BitmapAnd plan node; it can only appear as
+ * part of the substructure of a BitmapHeapPath.  The Path structure is
+ * a bit more heavyweight than we really need for this, but for simplicity
+ * we make it a derivative of Path anyway.
+ */
+typedef struct BitmapAndPath
+{
+	Path		path;
+	List	   *bitmapquals;	/* IndexPaths and BitmapOrPaths */
+	Selectivity bitmapselectivity;
+} BitmapAndPath;
+
+/*
+ * BitmapOrPath represents a BitmapOr plan node; it can only appear as
+ * part of the substructure of a BitmapHeapPath.  The Path structure is
+ * a bit more heavyweight than we really need for this, but for simplicity
+ * we make it a derivative of Path anyway.
+ */
+typedef struct BitmapOrPath
+{
+	Path		path;
+	List	   *bitmapquals;	/* IndexPaths and BitmapAndPaths */
+	Selectivity bitmapselectivity;
+} BitmapOrPath;
+
+/*
+ * TidPath represents a scan by TID
+ *
+ * tidquals is an implicitly OR'ed list of qual expressions of the form
+ * "CTID = pseudoconstant", or "CTID = ANY(pseudoconstant_array)",
+ * or a CurrentOfExpr for the relation.
+ */
+typedef struct TidPath
+{
+	Path		path;
+	List	   *tidquals;		/* qual(s) involving CTID = something */
+} TidPath;
+
+/*
+ * SubqueryScanPath represents a scan of an unflattened subquery-in-FROM
+ *
+ * Note that the subpath comes from a different planning domain; for example
+ * RTE indexes within it mean something different from those known to the
+ * SubqueryScanPath.  path.parent->subroot is the planning context needed to
+ * interpret the subpath.
+ */
+typedef struct SubqueryScanPath
+{
+	Path		path;
+	Path	   *subpath;		/* path representing subquery execution */
+} SubqueryScanPath;
+
+/*
+ * ForeignPath represents a potential scan of a foreign table, foreign join
+ * or foreign upper-relation.
+ *
+ * fdw_private stores FDW private data about the scan.  While fdw_private is
+ * not actually touched by the core code during normal operations, it's
+ * generally a good idea to use a representation that can be dumped by
+ * nodeToString(), so that you can examine the structure during debugging
+ * with tools like pprint().
+ */
+typedef struct ForeignPath
+{
+	Path		path;
+	Path	   *fdw_outerpath;
+	List	   *fdw_private;
+} ForeignPath;
+
+/*
+ * CustomPath represents a table scan done by some out-of-core extension.
+ *
+ * We provide a set of hooks here - which the provider must take care to set
+ * up correctly - to allow extensions to supply their own methods of scanning
+ * a relation.  For example, a provider might provide GPU acceleration, a
+ * cache-based scan, or some other kind of logic we haven't dreamed up yet.
+ *
+ * CustomPaths can be injected into the planning process for a relation by
+ * set_rel_pathlist_hook functions.
+ *
+ * Core code must avoid assuming that the CustomPath is only as large as
+ * the structure declared here; providers are allowed to make it the first
+ * element in a larger structure.  (Since the planner never copies Paths,
+ * this doesn't add any complication.)  However, for consistency with the
+ * FDW case, we provide a "custom_private" field in CustomPath; providers
+ * may prefer to use that rather than define another struct type.
+ */
+
+struct CustomPathMethods;
+
+typedef struct CustomPath
+{
+	Path		path;
+	uint32		flags;			/* mask of CUSTOMPATH_* flags, see
+								 * nodes/extensible.h */
+	List	   *custom_paths;	/* list of child Path nodes, if any */
+	List	   *custom_private;
+	const struct CustomPathMethods *methods;
+} CustomPath;
+
+/*
+ * AppendPath represents an Append plan, ie, successive execution of
+ * several member plans.
+ *
+ * For partial Append, 'subpaths' contains non-partial subpaths followed by
+ * partial subpaths.
+ *
+ * Note: it is possible for "subpaths" to contain only one, or even no,
+ * elements.  These cases are optimized during create_append_plan.
+ * In particular, an AppendPath with no subpaths is a "dummy" path that
+ * is created to represent the case that a relation is provably empty.
+ * (This is a convenient representation because it means that when we build
+ * an appendrel and find that all its children have been excluded, no extra
+ * action is needed to recognize the relation as dummy.)
+ */
+typedef struct AppendPath
+{
+	Path		path;
+	/* RT indexes of non-leaf tables in a partition tree */
+	List	   *partitioned_rels;
+	List	   *subpaths;		/* list of component Paths */
+	/* Index of first partial path in subpaths; list_length(subpaths) if none */
+	int			first_partial_path;
+	double		limit_tuples;	/* hard limit on output tuples, or -1 */
+} AppendPath;
+
+#define IS_DUMMY_APPEND(p) \
+	(IsA((p), AppendPath) && ((AppendPath *) (p))->subpaths == NIL)
+
+/*
+ * A relation that's been proven empty will have one path that is dummy
+ * (but might have projection paths on top).  For historical reasons,
+ * this is provided as a macro that wraps is_dummy_rel().
+ */
+#define IS_DUMMY_REL(r) is_dummy_rel(r)
+extern bool is_dummy_rel(RelOptInfo *rel);
+
+/*
+ * MergeAppendPath represents a MergeAppend plan, ie, the merging of sorted
+ * results from several member plans to produce similarly-sorted output.
+ */
+typedef struct MergeAppendPath
+{
+	Path		path;
+	/* RT indexes of non-leaf tables in a partition tree */
+	List	   *partitioned_rels;
+	List	   *subpaths;		/* list of component Paths */
+	double		limit_tuples;	/* hard limit on output tuples, or -1 */
+} MergeAppendPath;
+
+/*
+ * GroupResultPath represents use of a Result plan node to compute the
+ * output of a degenerate GROUP BY case, wherein we know we should produce
+ * exactly one row, which might then be filtered by a HAVING qual.
+ *
+ * Note that quals is a list of bare clauses, not RestrictInfos.
+ */
+typedef struct GroupResultPath
+{
+	Path		path;
+	List	   *quals;
+} GroupResultPath;
+
+/*
+ * MaterialPath represents use of a Material plan node, i.e., caching of
+ * the output of its subpath.  This is used when the subpath is expensive
+ * and needs to be scanned repeatedly, or when we need mark/restore ability
+ * and the subpath doesn't have it.
+ */
+typedef struct MaterialPath
+{
+	Path		path;
+	Path	   *subpath;
+} MaterialPath;
+
+/*
+ * UniquePath represents elimination of distinct rows from the output of
+ * its subpath.
+ *
+ * This can represent significantly different plans: either hash-based or
+ * sort-based implementation, or a no-op if the input path can be proven
+ * distinct already.  The decision is sufficiently localized that it's not
+ * worth having separate Path node types.  (Note: in the no-op case, we could
+ * eliminate the UniquePath node entirely and just return the subpath; but
+ * it's convenient to have a UniquePath in the path tree to signal upper-level
+ * routines that the input is known distinct.)
+ */
+typedef enum
+{
+	UNIQUE_PATH_NOOP,			/* input is known unique already */
+	UNIQUE_PATH_HASH,			/* use hashing */
+	UNIQUE_PATH_SORT			/* use sorting */
+} UniquePathMethod;
+
+typedef struct UniquePath
+{
+	Path		path;
+	Path	   *subpath;
+	UniquePathMethod umethod;
+	List	   *in_operators;	/* equality operators of the IN clause */
+	List	   *uniq_exprs;		/* expressions to be made unique */
+} UniquePath;
+
+/*
+ * GatherPath runs several copies of a plan in parallel and collects the
+ * results.  The parallel leader may also execute the plan, unless the
+ * single_copy flag is set.
+ */
+typedef struct GatherPath
+{
+	Path		path;
+	Path	   *subpath;		/* path for each worker */
+	bool		single_copy;	/* don't execute path more than once */
+	int			num_workers;	/* number of workers sought to help */
+} GatherPath;
+
+/*
+ * GatherMergePath runs several copies of a plan in parallel and collects
+ * the results, preserving their common sort order.
+ */
+typedef struct GatherMergePath
+{
+	Path		path;
+	Path	   *subpath;		/* path for each worker */
+	int			num_workers;	/* number of workers sought to help */
+} GatherMergePath;
+
+
+/*
+ * All join-type paths share these fields.
+ */
+
+typedef struct JoinPath
+{
+	Path		path;
+
+	JoinType	jointype;
+
+	bool		inner_unique;	/* each outer tuple provably matches no more
+								 * than one inner tuple */
+
+	Path	   *outerjoinpath;	/* path for the outer side of the join */
+	Path	   *innerjoinpath;	/* path for the inner side of the join */
+
+	List	   *joinrestrictinfo;	/* RestrictInfos to apply to join */
+
+	/*
+	 * See the notes for RelOptInfo and ParamPathInfo to understand why
+	 * joinrestrictinfo is needed in JoinPath, and can't be merged into the
+	 * parent RelOptInfo.
+	 */
+} JoinPath;
+
+/*
+ * A nested-loop path needs no special fields.
+ */
+
+typedef JoinPath NestPath;
+
+/*
+ * A mergejoin path has these fields.
+ *
+ * Unlike other path types, a MergePath node doesn't represent just a single
+ * run-time plan node: it can represent up to four.  Aside from the MergeJoin
+ * node itself, there can be a Sort node for the outer input, a Sort node
+ * for the inner input, and/or a Material node for the inner input.  We could
+ * represent these nodes by separate path nodes, but considering how many
+ * different merge paths are investigated during a complex join problem,
+ * it seems better to avoid unnecessary palloc overhead.
+ *
+ * path_mergeclauses lists the clauses (in the form of RestrictInfos)
+ * that will be used in the merge.
+ *
+ * Note that the mergeclauses are a subset of the parent relation's
+ * restriction-clause list.  Any join clauses that are not mergejoinable
+ * appear only in the parent's restrict list, and must be checked by a
+ * qpqual at execution time.
+ *
+ * outersortkeys (resp. innersortkeys) is NIL if the outer path
+ * (resp. inner path) is already ordered appropriately for the
+ * mergejoin.  If it is not NIL then it is a PathKeys list describing
+ * the ordering that must be created by an explicit Sort node.
+ *
+ * skip_mark_restore is true if the executor need not do mark/restore calls.
+ * Mark/restore overhead is usually required, but can be skipped if we know
+ * that the executor need find only one match per outer tuple, and that the
+ * mergeclauses are sufficient to identify a match.  In such cases the
+ * executor can immediately advance the outer relation after processing a
+ * match, and therefore it need never back up the inner relation.
+ *
+ * materialize_inner is true if a Material node should be placed atop the
+ * inner input.  This may appear with or without an inner Sort step.
+ */
+
+typedef struct MergePath
+{
+	JoinPath	jpath;
+	List	   *path_mergeclauses;	/* join clauses to be used for merge */
+	List	   *outersortkeys;	/* keys for explicit sort, if any */
+	List	   *innersortkeys;	/* keys for explicit sort, if any */
+	bool		skip_mark_restore;	/* can executor skip mark/restore? */
+	bool		materialize_inner;	/* add Materialize to inner? */
+} MergePath;
+
+/*
+ * A hashjoin path has these fields.
+ *
+ * The remarks above for mergeclauses apply for hashclauses as well.
+ *
+ * Hashjoin does not care what order its inputs appear in, so we have
+ * no need for sortkeys.
+ */
+
+typedef struct HashPath
+{
+	JoinPath	jpath;
+	List	   *path_hashclauses;	/* join clauses used for hashing */
+	int			num_batches;	/* number of batches expected */
+	double		inner_rows_total;	/* total inner rows expected */
+} HashPath;
+
+/*
+ * ProjectionPath represents a projection (that is, targetlist computation)
+ *
+ * Nominally, this path node represents using a Result plan node to do a
+ * projection step.  However, if the input plan node supports projection,
+ * we can just modify its output targetlist to do the required calculations
+ * directly, and not need a Result.  In some places in the planner we can just
+ * jam the desired PathTarget into the input path node (and adjust its cost
+ * accordingly), so we don't need a ProjectionPath.  But in other places
+ * it's necessary to not modify the input path node, so we need a separate
+ * ProjectionPath node, which is marked dummy to indicate that we intend to
+ * assign the work to the input plan node.  The estimated cost for the
+ * ProjectionPath node will account for whether a Result will be used or not.
+ */
+typedef struct ProjectionPath
+{
+	Path		path;
+	Path	   *subpath;		/* path representing input source */
+	bool		dummypp;		/* true if no separate Result is needed */
+} ProjectionPath;
+
+/*
+ * ProjectSetPath represents evaluation of a targetlist that includes
+ * set-returning function(s), which will need to be implemented by a
+ * ProjectSet plan node.
+ */
+typedef struct ProjectSetPath
+{
+	Path		path;
+	Path	   *subpath;		/* path representing input source */
+} ProjectSetPath;
+
+/*
+ * SortPath represents an explicit sort step
+ *
+ * The sort keys are, by definition, the same as path.pathkeys.
+ *
+ * Note: the Sort plan node cannot project, so path.pathtarget must be the
+ * same as the input's pathtarget.
+ */
+typedef struct SortPath
+{
+	Path		path;
+	Path	   *subpath;		/* path representing input source */
+} SortPath;
+
+/*
+ * IncrementalSortPath represents an incremental sort step
+ *
+ * This is like a regular sort, except some leading key columns are assumed
+ * to be ordered already.
+ */
+typedef struct IncrementalSortPath
+{
+	SortPath	spath;
+	int			nPresortedCols; /* number of presorted columns */
+} IncrementalSortPath;
+
+/*
+ * GroupPath represents grouping (of presorted input)
+ *
+ * groupClause represents the columns to be grouped on; the input path
+ * must be at least that well sorted.
+ *
+ * We can also apply a qual to the grouped rows (equivalent of HAVING)
+ */
+typedef struct GroupPath
+{
+	Path		path;
+	Path	   *subpath;		/* path representing input source */
+	List	   *groupClause;	/* a list of SortGroupClause's */
+	List	   *qual;			/* quals (HAVING quals), if any */
+} GroupPath;
+
+/*
+ * UpperUniquePath represents adjacent-duplicate removal (in presorted input)
+ *
+ * The columns to be compared are the first numkeys columns of the path's
+ * pathkeys.  The input is presumed already sorted that way.
+ */
+typedef struct UpperUniquePath
+{
+	Path		path;
+	Path	   *subpath;		/* path representing input source */
+	int			numkeys;		/* number of pathkey columns to compare */
+} UpperUniquePath;
+
+/*
+ * AggPath represents generic computation of aggregate functions
+ *
+ * This may involve plain grouping (but not grouping sets), using either
+ * sorted or hashed grouping; for the AGG_SORTED case, the input must be
+ * appropriately presorted.
+ */
+typedef struct AggPath
+{
+	Path		path;
+	Path	   *subpath;		/* path representing input source */
+	AggStrategy aggstrategy;	/* basic strategy, see nodes.h */
+	AggSplit	aggsplit;		/* agg-splitting mode, see nodes.h */
+	double		numGroups;		/* estimated number of groups in input */
+	uint64		transitionSpace;	/* for pass-by-ref transition data */
+	List	   *groupClause;	/* a list of SortGroupClause's */
+	List	   *qual;			/* quals (HAVING quals), if any */
+} AggPath;
+
+/*
+ * Various annotations used for grouping sets in the planner.
+ */
+
+typedef struct GroupingSetData
+{
+	NodeTag		type;
+	List	   *set;			/* grouping set as list of sortgrouprefs */
+	double		numGroups;		/* est. number of result groups */
+} GroupingSetData;
+
+typedef struct RollupData
+{
+	NodeTag		type;
+	List	   *groupClause;	/* applicable subset of parse->groupClause */
+	List	   *gsets;			/* lists of integer indexes into groupClause */
+	List	   *gsets_data;		/* list of GroupingSetData */
+	double		numGroups;		/* est. number of result groups */
+	bool		hashable;		/* can be hashed */
+	bool		is_hashed;		/* to be implemented as a hashagg */
+} RollupData;
+
+/*
+ * GroupingSetsPath represents a GROUPING SETS aggregation
+ */
+
+typedef struct GroupingSetsPath
+{
+	Path		path;
+	Path	   *subpath;		/* path representing input source */
+	AggStrategy aggstrategy;	/* basic strategy */
+	List	   *rollups;		/* list of RollupData */
+	List	   *qual;			/* quals (HAVING quals), if any */
+	uint64		transitionSpace;	/* for pass-by-ref transition data */
+} GroupingSetsPath;
+
+/*
+ * MinMaxAggPath represents computation of MIN/MAX aggregates from indexes
+ */
+typedef struct MinMaxAggPath
+{
+	Path		path;
+	List	   *mmaggregates;	/* list of MinMaxAggInfo */
+	List	   *quals;			/* HAVING quals, if any */
+} MinMaxAggPath;
+
+/*
+ * WindowAggPath represents generic computation of window functions
+ */
+typedef struct WindowAggPath
+{
+	Path		path;
+	Path	   *subpath;		/* path representing input source */
+	WindowClause *winclause;	/* WindowClause we'll be using */
+} WindowAggPath;
+
+/*
+ * SetOpPath represents a set-operation, that is INTERSECT or EXCEPT
+ */
+typedef struct SetOpPath
+{
+	Path		path;
+	Path	   *subpath;		/* path representing input source */
+	SetOpCmd	cmd;			/* what to do, see nodes.h */
+	SetOpStrategy strategy;		/* how to do it, see nodes.h */
+	List	   *distinctList;	/* SortGroupClauses identifying target cols */
+	AttrNumber	flagColIdx;		/* where is the flag column, if any */
+	int			firstFlag;		/* flag value for first input relation */
+	double		numGroups;		/* estimated number of groups in input */
+} SetOpPath;
+
+/*
+ * RecursiveUnionPath represents a recursive UNION node
+ */
+typedef struct RecursiveUnionPath
+{
+	Path		path;
+	Path	   *leftpath;		/* paths representing input sources */
+	Path	   *rightpath;
+	List	   *distinctList;	/* SortGroupClauses identifying target cols */
+	int			wtParam;		/* ID of Param representing work table */
+	double		numGroups;		/* estimated number of groups in input */
+} RecursiveUnionPath;
+
+/*
+ * LockRowsPath represents acquiring row locks for SELECT FOR UPDATE/SHARE
+ */
+typedef struct LockRowsPath
+{
+	Path		path;
+	Path	   *subpath;		/* path representing input source */
+	List	   *rowMarks;		/* a list of PlanRowMark's */
+	int			epqParam;		/* ID of Param for EvalPlanQual re-eval */
+} LockRowsPath;
+
+/*
+ * ModifyTablePath represents performing INSERT/UPDATE/DELETE modifications
+ *
+ * We represent most things that will be in the ModifyTable plan node
+ * literally, except we have child Path(s) not Plan(s).  But analysis of the
+ * OnConflictExpr is deferred to createplan.c, as is collection of FDW data.
+ */
+typedef struct ModifyTablePath
+{
+	Path		path;
+	CmdType		operation;		/* INSERT, UPDATE, or DELETE */
+	bool		canSetTag;		/* do we set the command tag/es_processed? */
+	Index		nominalRelation;	/* Parent RT index for use of EXPLAIN */
+	Index		rootRelation;	/* Root RT index, if target is partitioned */
+	bool		partColsUpdated;	/* some part key in hierarchy updated */
+	List	   *resultRelations;	/* integer list of RT indexes */
+	List	   *subpaths;		/* Path(s) producing source data */
+	List	   *subroots;		/* per-target-table PlannerInfos */
+	List	   *withCheckOptionLists;	/* per-target-table WCO lists */
+	List	   *returningLists; /* per-target-table RETURNING tlists */
+	List	   *rowMarks;		/* PlanRowMarks (non-locking only) */
+	OnConflictExpr *onconflict; /* ON CONFLICT clause, or NULL */
+	int			epqParam;		/* ID of Param for EvalPlanQual re-eval */
+} ModifyTablePath;
+
+/*
+ * LimitPath represents applying LIMIT/OFFSET restrictions
+ */
+typedef struct LimitPath
+{
+	Path		path;
+	Path	   *subpath;		/* path representing input source */
+	Node	   *limitOffset;	/* OFFSET parameter, or NULL if none */
+	Node	   *limitCount;		/* COUNT parameter, or NULL if none */
+	LimitOption limitOption;	/* FETCH FIRST with ties or exact number */
+} LimitPath;
+
+
+/*
+ * Restriction clause info.
+ *
+ * We create one of these for each AND sub-clause of a restriction condition
+ * (WHERE or JOIN/ON clause).  Since the restriction clauses are logically
+ * ANDed, we can use any one of them or any subset of them to filter out
+ * tuples, without having to evaluate the rest.  The RestrictInfo node itself
+ * stores data used by the optimizer while choosing the best query plan.
+ *
+ * If a restriction clause references a single base relation, it will appear
+ * in the baserestrictinfo list of the RelOptInfo for that base rel.
+ *
+ * If a restriction clause references more than one base rel, it will
+ * appear in the joininfo list of every RelOptInfo that describes a strict
+ * subset of the base rels mentioned in the clause.  The joininfo lists are
+ * used to drive join tree building by selecting plausible join candidates.
+ * The clause cannot actually be applied until we have built a join rel
+ * containing all the base rels it references, however.
+ *
+ * When we construct a join rel that includes all the base rels referenced
+ * in a multi-relation restriction clause, we place that clause into the
+ * joinrestrictinfo lists of paths for the join rel, if neither left nor
+ * right sub-path includes all base rels referenced in the clause.  The clause
+ * will be applied at that join level, and will not propagate any further up
+ * the join tree.  (Note: the "predicate migration" code was once intended to
+ * push restriction clauses up and down the plan tree based on evaluation
+ * costs, but it's dead code and is unlikely to be resurrected in the
+ * foreseeable future.)
+ *
+ * Note that in the presence of more than two rels, a multi-rel restriction
+ * might reach different heights in the join tree depending on the join
+ * sequence we use.  So, these clauses cannot be associated directly with
+ * the join RelOptInfo, but must be kept track of on a per-join-path basis.
+ *
+ * RestrictInfos that represent equivalence conditions (i.e., mergejoinable
+ * equalities that are not outerjoin-delayed) are handled a bit differently.
+ * Initially we attach them to the EquivalenceClasses that are derived from
+ * them.  When we construct a scan or join path, we look through all the
+ * EquivalenceClasses and generate derived RestrictInfos representing the
+ * minimal set of conditions that need to be checked for this particular scan
+ * or join to enforce that all members of each EquivalenceClass are in fact
+ * equal in all rows emitted by the scan or join.
+ *
+ * When dealing with outer joins we have to be very careful about pushing qual
+ * clauses up and down the tree.  An outer join's own JOIN/ON conditions must
+ * be evaluated exactly at that join node, unless they are "degenerate"
+ * conditions that reference only Vars from the nullable side of the join.
+ * Quals appearing in WHERE or in a JOIN above the outer join cannot be pushed
+ * down below the outer join, if they reference any nullable Vars.
+ * RestrictInfo nodes contain a flag to indicate whether a qual has been
+ * pushed down to a lower level than its original syntactic placement in the
+ * join tree would suggest.  If an outer join prevents us from pushing a qual
+ * down to its "natural" semantic level (the level associated with just the
+ * base rels used in the qual) then we mark the qual with a "required_relids"
+ * value including more than just the base rels it actually uses.  By
+ * pretending that the qual references all the rels required to form the outer
+ * join, we prevent it from being evaluated below the outer join's joinrel.
+ * When we do form the outer join's joinrel, we still need to distinguish
+ * those quals that are actually in that join's JOIN/ON condition from those
+ * that appeared elsewhere in the tree and were pushed down to the join rel
+ * because they used no other rels.  That's what the is_pushed_down flag is
+ * for; it tells us that a qual is not an OUTER JOIN qual for the set of base
+ * rels listed in required_relids.  A clause that originally came from WHERE
+ * or an INNER JOIN condition will *always* have its is_pushed_down flag set.
+ * It's possible for an OUTER JOIN clause to be marked is_pushed_down too,
+ * if we decide that it can be pushed down into the nullable side of the join.
+ * In that case it acts as a plain filter qual for wherever it gets evaluated.
+ * (In short, is_pushed_down is only false for non-degenerate outer join
+ * conditions.  Possibly we should rename it to reflect that meaning?  But
+ * see also the comments for RINFO_IS_PUSHED_DOWN, below.)
+ *
+ * RestrictInfo nodes also contain an outerjoin_delayed flag, which is true
+ * if the clause's applicability must be delayed due to any outer joins
+ * appearing below it (ie, it has to be postponed to some join level higher
+ * than the set of relations it actually references).
+ *
+ * There is also an outer_relids field, which is NULL except for outer join
+ * clauses; for those, it is the set of relids on the outer side of the
+ * clause's outer join.  (These are rels that the clause cannot be applied to
+ * in parameterized scans, since pushing it into the join's outer side would
+ * lead to wrong answers.)
+ *
+ * There is also a nullable_relids field, which is the set of rels the clause
+ * references that can be forced null by some outer join below the clause.
+ *
+ * outerjoin_delayed = true is subtly different from nullable_relids != NULL:
+ * a clause might reference some nullable rels and yet not be
+ * outerjoin_delayed because it also references all the other rels of the
+ * outer join(s). A clause that is not outerjoin_delayed can be enforced
+ * anywhere it is computable.
+ *
+ * To handle security-barrier conditions efficiently, we mark RestrictInfo
+ * nodes with a security_level field, in which higher values identify clauses
+ * coming from less-trusted sources.  The exact semantics are that a clause
+ * cannot be evaluated before another clause with a lower security_level value
+ * unless the first clause is leakproof.  As with outer-join clauses, this
+ * creates a reason for clauses to sometimes need to be evaluated higher in
+ * the join tree than their contents would suggest; and even at a single plan
+ * node, this rule constrains the order of application of clauses.
+ *
+ * In general, the referenced clause might be arbitrarily complex.  The
+ * kinds of clauses we can handle as indexscan quals, mergejoin clauses,
+ * or hashjoin clauses are limited (e.g., no volatile functions).  The code
+ * for each kind of path is responsible for identifying the restrict clauses
+ * it can use and ignoring the rest.  Clauses not implemented by an indexscan,
+ * mergejoin, or hashjoin will be placed in the plan qual or joinqual field
+ * of the finished Plan node, where they will be enforced by general-purpose
+ * qual-expression-evaluation code.  (But we are still entitled to count
+ * their selectivity when estimating the result tuple count, if we
+ * can guess what it is...)
+ *
+ * When the referenced clause is an OR clause, we generate a modified copy
+ * in which additional RestrictInfo nodes are inserted below the top-level
+ * OR/AND structure.  This is a convenience for OR indexscan processing:
+ * indexquals taken from either the top level or an OR subclause will have
+ * associated RestrictInfo nodes.
+ *
+ * The can_join flag is set true if the clause looks potentially useful as
+ * a merge or hash join clause, that is if it is a binary opclause with
+ * nonoverlapping sets of relids referenced in the left and right sides.
+ * (Whether the operator is actually merge or hash joinable isn't checked,
+ * however.)
+ *
+ * The pseudoconstant flag is set true if the clause contains no Vars of
+ * the current query level and no volatile functions.  Such a clause can be
+ * pulled out and used as a one-time qual in a gating Result node.  We keep
+ * pseudoconstant clauses in the same lists as other RestrictInfos so that
+ * the regular clause-pushing machinery can assign them to the correct join
+ * level, but they need to be treated specially for cost and selectivity
+ * estimates.  Note that a pseudoconstant clause can never be an indexqual
+ * or merge or hash join clause, so it's of no interest to large parts of
+ * the planner.
+ *
+ * When join clauses are generated from EquivalenceClasses, there may be
+ * several equally valid ways to enforce join equivalence, of which we need
+ * apply only one.  We mark clauses of this kind by setting parent_ec to
+ * point to the generating EquivalenceClass.  Multiple clauses with the same
+ * parent_ec in the same join are redundant.
+ */
+
+typedef struct RestrictInfo
+{
+	NodeTag		type;
+
+	Expr	   *clause;			/* the represented clause of WHERE or JOIN */
+
+	bool		is_pushed_down; /* true if clause was pushed down in level */
+
+	bool		outerjoin_delayed;	/* true if delayed by lower outer join */
+
+	bool		can_join;		/* see comment above */
+
+	bool		pseudoconstant; /* see comment above */
+
+	bool		leakproof;		/* true if known to contain no leaked Vars */
+
+	Index		security_level; /* see comment above */
+
+	/* The set of relids (varnos) actually referenced in the clause: */
+	Relids		clause_relids;
+
+	/* The set of relids required to evaluate the clause: */
+	Relids		required_relids;
+
+	/* If an outer-join clause, the outer-side relations, else NULL: */
+	Relids		outer_relids;
+
+	/* The relids used in the clause that are nullable by lower outer joins: */
+	Relids		nullable_relids;
+
+	/* These fields are set for any binary opclause: */
+	Relids		left_relids;	/* relids in left side of clause */
+	Relids		right_relids;	/* relids in right side of clause */
+
+	/* This field is NULL unless clause is an OR clause: */
+	Expr	   *orclause;		/* modified clause with RestrictInfos */
+
+	/* This field is NULL unless clause is potentially redundant: */
+	EquivalenceClass *parent_ec;	/* generating EquivalenceClass */
+
+	/* cache space for cost and selectivity */
+	QualCost	eval_cost;		/* eval cost of clause; -1 if not yet set */
+	Selectivity norm_selec;		/* selectivity for "normal" (JOIN_INNER)
+								 * semantics; -1 if not yet set; >1 means a
+								 * redundant clause */
+	Selectivity outer_selec;	/* selectivity for outer join semantics; -1 if
+								 * not yet set */
+
+	/* valid if clause is mergejoinable, else NIL */
+	List	   *mergeopfamilies;	/* opfamilies containing clause operator */
+
+	/* cache space for mergeclause processing; NULL if not yet set */
+	EquivalenceClass *left_ec;	/* EquivalenceClass containing lefthand */
+	EquivalenceClass *right_ec; /* EquivalenceClass containing righthand */
+	EquivalenceMember *left_em; /* EquivalenceMember for lefthand */
+	EquivalenceMember *right_em;	/* EquivalenceMember for righthand */
+	List	   *scansel_cache;	/* list of MergeScanSelCache structs */
+
+	/* transient workspace for use while considering a specific join path */
+	bool		outer_is_left;	/* T = outer var on left, F = on right */
+
+	/* valid if clause is hashjoinable, else InvalidOid: */
+	Oid			hashjoinoperator;	/* copy of clause operator */
+
+	/* cache space for hashclause processing; -1 if not yet set */
+	Selectivity left_bucketsize;	/* avg bucketsize of left side */
+	Selectivity right_bucketsize;	/* avg bucketsize of right side */
+	Selectivity left_mcvfreq;	/* left side's most common val's freq */
+	Selectivity right_mcvfreq;	/* right side's most common val's freq */
+} RestrictInfo;
+
+/*
+ * This macro embodies the correct way to test whether a RestrictInfo is
+ * "pushed down" to a given outer join, that is, should be treated as a filter
+ * clause rather than a join clause at that outer join.  This is certainly so
+ * if is_pushed_down is true; but examining that is not sufficient anymore,
+ * because outer-join clauses will get pushed down to lower outer joins when
+ * we generate a path for the lower outer join that is parameterized by the
+ * LHS of the upper one.  We can detect such a clause by noting that its
+ * required_relids exceed the scope of the join.
+ */
+#define RINFO_IS_PUSHED_DOWN(rinfo, joinrelids) \
+	((rinfo)->is_pushed_down || \
+	 !bms_is_subset((rinfo)->required_relids, joinrelids))
+
+/*
+ * Since mergejoinscansel() is a relatively expensive function, and would
+ * otherwise be invoked many times while planning a large join tree,
+ * we go out of our way to cache its results.  Each mergejoinable
+ * RestrictInfo carries a list of the specific sort orderings that have
+ * been considered for use with it, and the resulting selectivities.
+ */
+typedef struct MergeScanSelCache
+{
+	/* Ordering details (cache lookup key) */
+	Oid			opfamily;		/* btree opfamily defining the ordering */
+	Oid			collation;		/* collation for the ordering */
+	int			strategy;		/* sort direction (ASC or DESC) */
+	bool		nulls_first;	/* do NULLs come before normal values? */
+	/* Results */
+	Selectivity leftstartsel;	/* first-join fraction for clause left side */
+	Selectivity leftendsel;		/* last-join fraction for clause left side */
+	Selectivity rightstartsel;	/* first-join fraction for clause right side */
+	Selectivity rightendsel;	/* last-join fraction for clause right side */
+} MergeScanSelCache;
+
+/*
+ * Placeholder node for an expression to be evaluated below the top level
+ * of a plan tree.  This is used during planning to represent the contained
+ * expression.  At the end of the planning process it is replaced by either
+ * the contained expression or a Var referring to a lower-level evaluation of
+ * the contained expression.  Typically the evaluation occurs below an outer
+ * join, and Var references above the outer join might thereby yield NULL
+ * instead of the expression value.
+ *
+ * Although the planner treats this as an expression node type, it is not
+ * recognized by the parser or executor, so we declare it here rather than
+ * in primnodes.h.
+ */
+
+typedef struct PlaceHolderVar
+{
+	Expr		xpr;
+	Expr	   *phexpr;			/* the represented expression */
+	Relids		phrels;			/* base relids syntactically within expr src */
+	Index		phid;			/* ID for PHV (unique within planner run) */
+	Index		phlevelsup;		/* > 0 if PHV belongs to outer query */
+} PlaceHolderVar;
+
+/*
+ * "Special join" info.
+ *
+ * One-sided outer joins constrain the order of joining partially but not
+ * completely.  We flatten such joins into the planner's top-level list of
+ * relations to join, but record information about each outer join in a
+ * SpecialJoinInfo struct.  These structs are kept in the PlannerInfo node's
+ * join_info_list.
+ *
+ * Similarly, semijoins and antijoins created by flattening IN (subselect)
+ * and EXISTS(subselect) clauses create partial constraints on join order.
+ * These are likewise recorded in SpecialJoinInfo structs.
+ *
+ * We make SpecialJoinInfos for FULL JOINs even though there is no flexibility
+ * of planning for them, because this simplifies make_join_rel()'s API.
+ *
+ * min_lefthand and min_righthand are the sets of base relids that must be
+ * available on each side when performing the special join.  lhs_strict is
+ * true if the special join's condition cannot succeed when the LHS variables
+ * are all NULL (this means that an outer join can commute with upper-level
+ * outer joins even if it appears in their RHS).  We don't bother to set
+ * lhs_strict for FULL JOINs, however.
+ *
+ * It is not valid for either min_lefthand or min_righthand to be empty sets;
+ * if they were, this would break the logic that enforces join order.
+ *
+ * syn_lefthand and syn_righthand are the sets of base relids that are
+ * syntactically below this special join.  (These are needed to help compute
+ * min_lefthand and min_righthand for higher joins.)
+ *
+ * delay_upper_joins is set true if we detect a pushed-down clause that has
+ * to be evaluated after this join is formed (because it references the RHS).
+ * Any outer joins that have such a clause and this join in their RHS cannot
+ * commute with this join, because that would leave noplace to check the
+ * pushed-down clause.  (We don't track this for FULL JOINs, either.)
+ *
+ * For a semijoin, we also extract the join operators and their RHS arguments
+ * and set semi_operators, semi_rhs_exprs, semi_can_btree, and semi_can_hash.
+ * This is done in support of possibly unique-ifying the RHS, so we don't
+ * bother unless at least one of semi_can_btree and semi_can_hash can be set
+ * true.  (You might expect that this information would be computed during
+ * join planning; but it's helpful to have it available during planning of
+ * parameterized table scans, so we store it in the SpecialJoinInfo structs.)
+ *
+ * jointype is never JOIN_RIGHT; a RIGHT JOIN is handled by switching
+ * the inputs to make it a LEFT JOIN.  So the allowed values of jointype
+ * in a join_info_list member are only LEFT, FULL, SEMI, or ANTI.
+ *
+ * For purposes of join selectivity estimation, we create transient
+ * SpecialJoinInfo structures for regular inner joins; so it is possible
+ * to have jointype == JOIN_INNER in such a structure, even though this is
+ * not allowed within join_info_list.  We also create transient
+ * SpecialJoinInfos with jointype == JOIN_INNER for outer joins, since for
+ * cost estimation purposes it is sometimes useful to know the join size under
+ * plain innerjoin semantics.  Note that lhs_strict, delay_upper_joins, and
+ * of course the semi_xxx fields are not set meaningfully within such structs.
+ */
+#ifndef HAVE_SPECIALJOININFO_TYPEDEF
+typedef struct SpecialJoinInfo SpecialJoinInfo;
+#define HAVE_SPECIALJOININFO_TYPEDEF 1
+#endif
+
+struct SpecialJoinInfo
+{
+	NodeTag		type;
+	Relids		min_lefthand;	/* base relids in minimum LHS for join */
+	Relids		min_righthand;	/* base relids in minimum RHS for join */
+	Relids		syn_lefthand;	/* base relids syntactically within LHS */
+	Relids		syn_righthand;	/* base relids syntactically within RHS */
+	JoinType	jointype;		/* always INNER, LEFT, FULL, SEMI, or ANTI */
+	bool		lhs_strict;		/* joinclause is strict for some LHS rel */
+	bool		delay_upper_joins;	/* can't commute with upper RHS */
+	/* Remaining fields are set only for JOIN_SEMI jointype: */
+	bool		semi_can_btree; /* true if semi_operators are all btree */
+	bool		semi_can_hash;	/* true if semi_operators are all hash */
+	List	   *semi_operators; /* OIDs of equality join operators */
+	List	   *semi_rhs_exprs; /* righthand-side expressions of these ops */
+};
+
+/*
+ * Append-relation info.
+ *
+ * When we expand an inheritable table or a UNION-ALL subselect into an
+ * "append relation" (essentially, a list of child RTEs), we build an
+ * AppendRelInfo for each child RTE.  The list of AppendRelInfos indicates
+ * which child RTEs must be included when expanding the parent, and each node
+ * carries information needed to translate between columns of the parent and
+ * columns of the child.
+ *
+ * These structs are kept in the PlannerInfo node's append_rel_list, with
+ * append_rel_array[] providing a convenient lookup method for the struct
+ * associated with a particular child relid (there can be only one, though
+ * parent rels may have many entries in append_rel_list).
+ *
+ * Note: after completion of the planner prep phase, any given RTE is an
+ * append parent having entries in append_rel_list if and only if its
+ * "inh" flag is set.  We clear "inh" for plain tables that turn out not
+ * to have inheritance children, and (in an abuse of the original meaning
+ * of the flag) we set "inh" for subquery RTEs that turn out to be
+ * flattenable UNION ALL queries.  This lets us avoid useless searches
+ * of append_rel_list.
+ *
+ * Note: the data structure assumes that append-rel members are single
+ * baserels.  This is OK for inheritance, but it prevents us from pulling
+ * up a UNION ALL member subquery if it contains a join.  While that could
+ * be fixed with a more complex data structure, at present there's not much
+ * point because no improvement in the plan could result.
+ */
+
+typedef struct AppendRelInfo
+{
+	NodeTag		type;
+
+	/*
+	 * These fields uniquely identify this append relationship.  There can be
+	 * (in fact, always should be) multiple AppendRelInfos for the same
+	 * parent_relid, but never more than one per child_relid, since a given
+	 * RTE cannot be a child of more than one append parent.
+	 */
+	Index		parent_relid;	/* RT index of append parent rel */
+	Index		child_relid;	/* RT index of append child rel */
+
+	/*
+	 * For an inheritance appendrel, the parent and child are both regular
+	 * relations, and we store their rowtype OIDs here for use in translating
+	 * whole-row Vars.  For a UNION-ALL appendrel, the parent and child are
+	 * both subqueries with no named rowtype, and we store InvalidOid here.
+	 */
+	Oid			parent_reltype; /* OID of parent's composite type */
+	Oid			child_reltype;	/* OID of child's composite type */
+
+	/*
+	 * The N'th element of this list is a Var or expression representing the
+	 * child column corresponding to the N'th column of the parent. This is
+	 * used to translate Vars referencing the parent rel into references to
+	 * the child.  A list element is NULL if it corresponds to a dropped
+	 * column of the parent (this is only possible for inheritance cases, not
+	 * UNION ALL).  The list elements are always simple Vars for inheritance
+	 * cases, but can be arbitrary expressions in UNION ALL cases.
+	 *
+	 * Notice we only store entries for user columns (attno > 0).  Whole-row
+	 * Vars are special-cased, and system columns (attno < 0) need no special
+	 * translation since their attnos are the same for all tables.
+	 *
+	 * Caution: the Vars have varlevelsup = 0.  Be careful to adjust as needed
+	 * when copying into a subquery.
+	 */
+	List	   *translated_vars;	/* Expressions in the child's Vars */
+
+	/*
+	 * This array simplifies translations in the reverse direction, from
+	 * child's column numbers to parent's.  The entry at [ccolno - 1] is the
+	 * 1-based parent column number for child column ccolno, or zero if that
+	 * child column is dropped or doesn't exist in the parent.
+	 */
+	int			num_child_cols; /* length of array */
+	AttrNumber *parent_colnos;	/* array of parent attnos, or zeroes */
+
+	/*
+	 * We store the parent table's OID here for inheritance, or InvalidOid for
+	 * UNION ALL.  This is only needed to help in generating error messages if
+	 * an attempt is made to reference a dropped parent column.
+	 */
+	Oid			parent_reloid;	/* OID of parent relation */
+} AppendRelInfo;
+
+/*
+ * For each distinct placeholder expression generated during planning, we
+ * store a PlaceHolderInfo node in the PlannerInfo node's placeholder_list.
+ * This stores info that is needed centrally rather than in each copy of the
+ * PlaceHolderVar.  The phid fields identify which PlaceHolderInfo goes with
+ * each PlaceHolderVar.  Note that phid is unique throughout a planner run,
+ * not just within a query level --- this is so that we need not reassign ID's
+ * when pulling a subquery into its parent.
+ *
+ * The idea is to evaluate the expression at (only) the ph_eval_at join level,
+ * then allow it to bubble up like a Var until the ph_needed join level.
+ * ph_needed has the same definition as attr_needed for a regular Var.
+ *
+ * The PlaceHolderVar's expression might contain LATERAL references to vars
+ * coming from outside its syntactic scope.  If so, those rels are *not*
+ * included in ph_eval_at, but they are recorded in ph_lateral.
+ *
+ * Notice that when ph_eval_at is a join rather than a single baserel, the
+ * PlaceHolderInfo may create constraints on join order: the ph_eval_at join
+ * has to be formed below any outer joins that should null the PlaceHolderVar.
+ *
+ * We create a PlaceHolderInfo only after determining that the PlaceHolderVar
+ * is actually referenced in the plan tree, so that unreferenced placeholders
+ * don't result in unnecessary constraints on join order.
+ */
+
+typedef struct PlaceHolderInfo
+{
+	NodeTag		type;
+
+	Index		phid;			/* ID for PH (unique within planner run) */
+	PlaceHolderVar *ph_var;		/* copy of PlaceHolderVar tree */
+	Relids		ph_eval_at;		/* lowest level we can evaluate value at */
+	Relids		ph_lateral;		/* relids of contained lateral refs, if any */
+	Relids		ph_needed;		/* highest level the value is needed at */
+	int32		ph_width;		/* estimated attribute width */
+} PlaceHolderInfo;
+
+/*
+ * This struct describes one potentially index-optimizable MIN/MAX aggregate
+ * function.  MinMaxAggPath contains a list of these, and if we accept that
+ * path, the list is stored into root->minmax_aggs for use during setrefs.c.
+ */
+typedef struct MinMaxAggInfo
+{
+	NodeTag		type;
+
+	Oid			aggfnoid;		/* pg_proc Oid of the aggregate */
+	Oid			aggsortop;		/* Oid of its sort operator */
+	Expr	   *target;			/* expression we are aggregating on */
+	PlannerInfo *subroot;		/* modified "root" for planning the subquery */
+	Path	   *path;			/* access path for subquery */
+	Cost		pathcost;		/* estimated cost to fetch first row */
+	Param	   *param;			/* param for subplan's output */
+} MinMaxAggInfo;
+
+/*
+ * At runtime, PARAM_EXEC slots are used to pass values around from one plan
+ * node to another.  They can be used to pass values down into subqueries (for
+ * outer references in subqueries), or up out of subqueries (for the results
+ * of a subplan), or from a NestLoop plan node into its inner relation (when
+ * the inner scan is parameterized with values from the outer relation).
+ * The planner is responsible for assigning nonconflicting PARAM_EXEC IDs to
+ * the PARAM_EXEC Params it generates.
+ *
+ * Outer references are managed via root->plan_params, which is a list of
+ * PlannerParamItems.  While planning a subquery, each parent query level's
+ * plan_params contains the values required from it by the current subquery.
+ * During create_plan(), we use plan_params to track values that must be
+ * passed from outer to inner sides of NestLoop plan nodes.
+ *
+ * The item a PlannerParamItem represents can be one of three kinds:
+ *
+ * A Var: the slot represents a variable of this level that must be passed
+ * down because subqueries have outer references to it, or must be passed
+ * from a NestLoop node to its inner scan.  The varlevelsup value in the Var
+ * will always be zero.
+ *
+ * A PlaceHolderVar: this works much like the Var case, except that the
+ * entry is a PlaceHolderVar node with a contained expression.  The PHV
+ * will have phlevelsup = 0, and the contained expression is adjusted
+ * to match in level.
+ *
+ * An Aggref (with an expression tree representing its argument): the slot
+ * represents an aggregate expression that is an outer reference for some
+ * subquery.  The Aggref itself has agglevelsup = 0, and its argument tree
+ * is adjusted to match in level.
+ *
+ * Note: we detect duplicate Var and PlaceHolderVar parameters and coalesce
+ * them into one slot, but we do not bother to do that for Aggrefs.
+ * The scope of duplicate-elimination only extends across the set of
+ * parameters passed from one query level into a single subquery, or for
+ * nestloop parameters across the set of nestloop parameters used in a single
+ * query level.  So there is no possibility of a PARAM_EXEC slot being used
+ * for conflicting purposes.
+ *
+ * In addition, PARAM_EXEC slots are assigned for Params representing outputs
+ * from subplans (values that are setParam items for those subplans).  These
+ * IDs need not be tracked via PlannerParamItems, since we do not need any
+ * duplicate-elimination nor later processing of the represented expressions.
+ * Instead, we just record the assignment of the slot number by appending to
+ * root->glob->paramExecTypes.
+ */
+typedef struct PlannerParamItem
+{
+	NodeTag		type;
+
+	Node	   *item;			/* the Var, PlaceHolderVar, or Aggref */
+	int			paramId;		/* its assigned PARAM_EXEC slot number */
+} PlannerParamItem;
+
+/*
+ * When making cost estimates for a SEMI/ANTI/inner_unique join, there are
+ * some correction factors that are needed in both nestloop and hash joins
+ * to account for the fact that the executor can stop scanning inner rows
+ * as soon as it finds a match to the current outer row.  These numbers
+ * depend only on the selected outer and inner join relations, not on the
+ * particular paths used for them, so it's worthwhile to calculate them
+ * just once per relation pair not once per considered path.  This struct
+ * is filled by compute_semi_anti_join_factors and must be passed along
+ * to the join cost estimation functions.
+ *
+ * outer_match_frac is the fraction of the outer tuples that are
+ *		expected to have at least one match.
+ * match_count is the average number of matches expected for
+ *		outer tuples that have at least one match.
+ */
+typedef struct SemiAntiJoinFactors
+{
+	Selectivity outer_match_frac;
+	Selectivity match_count;
+} SemiAntiJoinFactors;
+
+/*
+ * Struct for extra information passed to subroutines of add_paths_to_joinrel
+ *
+ * restrictlist contains all of the RestrictInfo nodes for restriction
+ *		clauses that apply to this join
+ * mergeclause_list is a list of RestrictInfo nodes for available
+ *		mergejoin clauses in this join
+ * inner_unique is true if each outer tuple provably matches no more
+ *		than one inner tuple
+ * sjinfo is extra info about special joins for selectivity estimation
+ * semifactors is as shown above (only valid for SEMI/ANTI/inner_unique joins)
+ * param_source_rels are OK targets for parameterization of result paths
+ */
+typedef struct JoinPathExtraData
+{
+	List	   *restrictlist;
+	List	   *mergeclause_list;
+	bool		inner_unique;
+	SpecialJoinInfo *sjinfo;
+	SemiAntiJoinFactors semifactors;
+	Relids		param_source_rels;
+} JoinPathExtraData;
+
+/*
+ * Various flags indicating what kinds of grouping are possible.
+ *
+ * GROUPING_CAN_USE_SORT should be set if it's possible to perform
+ * sort-based implementations of grouping.  When grouping sets are in use,
+ * this will be true if sorting is potentially usable for any of the grouping
+ * sets, even if it's not usable for all of them.
+ *
+ * GROUPING_CAN_USE_HASH should be set if it's possible to perform
+ * hash-based implementations of grouping.
+ *
+ * GROUPING_CAN_PARTIAL_AGG should be set if the aggregation is of a type
+ * for which we support partial aggregation (not, for example, grouping sets).
+ * It says nothing about parallel-safety or the availability of suitable paths.
+ */
+#define GROUPING_CAN_USE_SORT       0x0001
+#define GROUPING_CAN_USE_HASH       0x0002
+#define GROUPING_CAN_PARTIAL_AGG	0x0004
+
+/*
+ * What kind of partitionwise aggregation is in use?
+ *
+ * PARTITIONWISE_AGGREGATE_NONE: Not used.
+ *
+ * PARTITIONWISE_AGGREGATE_FULL: Aggregate each partition separately, and
+ * append the results.
+ *
+ * PARTITIONWISE_AGGREGATE_PARTIAL: Partially aggregate each partition
+ * separately, append the results, and then finalize aggregation.
+ */
+typedef enum
+{
+	PARTITIONWISE_AGGREGATE_NONE,
+	PARTITIONWISE_AGGREGATE_FULL,
+	PARTITIONWISE_AGGREGATE_PARTIAL
+} PartitionwiseAggregateType;
+
+/*
+ * Struct for extra information passed to subroutines of create_grouping_paths
+ *
+ * flags indicating what kinds of grouping are possible.
+ * partial_costs_set is true if the agg_partial_costs and agg_final_costs
+ * 		have been initialized.
+ * agg_partial_costs gives partial aggregation costs.
+ * agg_final_costs gives finalization costs.
+ * target_parallel_safe is true if target is parallel safe.
+ * havingQual gives list of quals to be applied after aggregation.
+ * targetList gives list of columns to be projected.
+ * patype is the type of partitionwise aggregation that is being performed.
+ */
+typedef struct
+{
+	/* Data which remains constant once set. */
+	int			flags;
+	bool		partial_costs_set;
+	AggClauseCosts agg_partial_costs;
+	AggClauseCosts agg_final_costs;
+
+	/* Data which may differ across partitions. */
+	bool		target_parallel_safe;
+	Node	   *havingQual;
+	List	   *targetList;
+	PartitionwiseAggregateType patype;
+} GroupPathExtraData;
+
+/*
+ * Struct for extra information passed to subroutines of grouping_planner
+ *
+ * limit_needed is true if we actually need a Limit plan node.
+ * limit_tuples is an estimated bound on the number of output tuples,
+ *		or -1 if no LIMIT or couldn't estimate.
+ * count_est and offset_est are the estimated values of the LIMIT and OFFSET
+ * 		expressions computed by preprocess_limit() (see comments for
+ * 		preprocess_limit() for more information).
+ */
+typedef struct
+{
+	bool		limit_needed;
+	double		limit_tuples;
+	int64		count_est;
+	int64		offset_est;
+} FinalPathExtraData;
+
+/*
+ * For speed reasons, cost estimation for join paths is performed in two
+ * phases: the first phase tries to quickly derive a lower bound for the
+ * join cost, and then we check if that's sufficient to reject the path.
+ * If not, we come back for a more refined cost estimate.  The first phase
+ * fills a JoinCostWorkspace struct with its preliminary cost estimates
+ * and possibly additional intermediate values.  The second phase takes
+ * these values as inputs to avoid repeating work.
+ *
+ * (Ideally we'd declare this in cost.h, but it's also needed in pathnode.h,
+ * so seems best to put it here.)
+ */
+typedef struct JoinCostWorkspace
+{
+	/* Preliminary cost estimates --- must not be larger than final ones! */
+	Cost		startup_cost;	/* cost expended before fetching any tuples */
+	Cost		total_cost;		/* total cost (assuming all tuples fetched) */
+
+	/* Fields below here should be treated as private to costsize.c */
+	Cost		run_cost;		/* non-startup cost components */
+
+	/* private for cost_nestloop code */
+	Cost		inner_run_cost; /* also used by cost_mergejoin code */
+	Cost		inner_rescan_run_cost;
+
+	/* private for cost_mergejoin code */
+	double		outer_rows;
+	double		inner_rows;
+	double		outer_skip_rows;
+	double		inner_skip_rows;
+
+	/* private for cost_hashjoin code */
+	int			numbuckets;
+	int			numbatches;
+	double		inner_rows_total;
+} JoinCostWorkspace;
+
+#endif							/* PATHNODES_H */
diff --git a/src/include/nodes/pg_list.h b/src/include/nodes/pg_list.h
new file mode 100644
index 0000000..54447bb
--- /dev/null
+++ b/src/include/nodes/pg_list.h
@@ -0,0 +1,605 @@
+/*-------------------------------------------------------------------------
+ *
+ * pg_list.h
+ *	  interface for PostgreSQL generic list package
+ *
+ * Once upon a time, parts of Postgres were written in Lisp and used real
+ * cons-cell lists for major data structures.  When that code was rewritten
+ * in C, we initially had a faithful emulation of cons-cell lists, which
+ * unsurprisingly was a performance bottleneck.  A couple of major rewrites
+ * later, these data structures are actually simple expansible arrays;
+ * but the "List" name and a lot of the notation survives.
+ *
+ * One important concession to the original implementation is that an empty
+ * list is always represented by a null pointer (preferentially written NIL).
+ * Non-empty lists have a header, which will not be relocated as long as the
+ * list remains non-empty, and an expansible data array.
+ *
+ * We support three types of lists:
+ *
+ *	T_List: lists of pointers
+ *		(in practice usually pointers to Nodes, but not always;
+ *		declared as "void *" to minimize casting annoyances)
+ *	T_IntList: lists of integers
+ *	T_OidList: lists of Oids
+ *
+ * (At the moment, ints and Oids are the same size, but they may not
+ * always be so; try to be careful to maintain the distinction.)
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/pg_list.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef PG_LIST_H
+#define PG_LIST_H
+
+#include "nodes/nodes.h"
+
+
+typedef union ListCell
+{
+	void	   *ptr_value;
+	int			int_value;
+	Oid			oid_value;
+} ListCell;
+
+typedef struct List
+{
+	NodeTag		type;			/* T_List, T_IntList, or T_OidList */
+	int			length;			/* number of elements currently present */
+	int			max_length;		/* allocated length of elements[] */
+	ListCell   *elements;		/* re-allocatable array of cells */
+	/* We may allocate some cells along with the List header: */
+	ListCell	initial_elements[FLEXIBLE_ARRAY_MEMBER];
+	/* If elements == initial_elements, it's not a separate allocation */
+} List;
+
+/*
+ * The *only* valid representation of an empty list is NIL; in other
+ * words, a non-NIL list is guaranteed to have length >= 1.
+ */
+#define NIL						((List *) NULL)
+
+/*
+ * State structs for various looping macros below.
+ */
+typedef struct ForEachState
+{
+	const List *l;				/* list we're looping through */
+	int			i;				/* current element index */
+} ForEachState;
+
+typedef struct ForBothState
+{
+	const List *l1;				/* lists we're looping through */
+	const List *l2;
+	int			i;				/* common element index */
+} ForBothState;
+
+typedef struct ForBothCellState
+{
+	const List *l1;				/* lists we're looping through */
+	const List *l2;
+	int			i1;				/* current element indexes */
+	int			i2;
+} ForBothCellState;
+
+typedef struct ForThreeState
+{
+	const List *l1;				/* lists we're looping through */
+	const List *l2;
+	const List *l3;
+	int			i;				/* common element index */
+} ForThreeState;
+
+typedef struct ForFourState
+{
+	const List *l1;				/* lists we're looping through */
+	const List *l2;
+	const List *l3;
+	const List *l4;
+	int			i;				/* common element index */
+} ForFourState;
+
+typedef struct ForFiveState
+{
+	const List *l1;				/* lists we're looping through */
+	const List *l2;
+	const List *l3;
+	const List *l4;
+	const List *l5;
+	int			i;				/* common element index */
+} ForFiveState;
+
+/*
+ * These routines are small enough, and used often enough, to justify being
+ * inline.
+ */
+
+/* Fetch address of list's first cell; NULL if empty list */
+static inline ListCell *
+list_head(const List *l)
+{
+	return l ? &l->elements[0] : NULL;
+}
+
+/* Fetch address of list's last cell; NULL if empty list */
+static inline ListCell *
+list_tail(const List *l)
+{
+	return l ? &l->elements[l->length - 1] : NULL;
+}
+
+/* Fetch address of list's second cell, if it has one, else NULL */
+static inline ListCell *
+list_second_cell(const List *l)
+{
+	if (l && l->length >= 2)
+		return &l->elements[1];
+	else
+		return NULL;
+}
+
+/* Fetch address of list's third cell, if it has one, else NULL */
+static inline ListCell *
+list_third_cell(const List *l)
+{
+	if (l && l->length >= 3)
+		return &l->elements[2];
+	else
+		return NULL;
+}
+
+/* Fetch address of list's fourth cell, if it has one, else NULL */
+static inline ListCell *
+list_fourth_cell(const List *l)
+{
+	if (l && l->length >= 4)
+		return &l->elements[3];
+	else
+		return NULL;
+}
+
+/* Fetch list's length */
+static inline int
+list_length(const List *l)
+{
+	return l ? l->length : 0;
+}
+
+/*
+ * Macros to access the data values within List cells.
+ *
+ * Note that with the exception of the "xxx_node" macros, these are
+ * lvalues and can be assigned to.
+ *
+ * NB: There is an unfortunate legacy from a previous incarnation of
+ * the List API: the macro lfirst() was used to mean "the data in this
+ * cons cell". To avoid changing every usage of lfirst(), that meaning
+ * has been kept. As a result, lfirst() takes a ListCell and returns
+ * the data it contains; to get the data in the first cell of a
+ * List, use linitial(). Worse, lsecond() is more closely related to
+ * linitial() than lfirst(): given a List, lsecond() returns the data
+ * in the second list cell.
+ */
+
+#define lfirst(lc)				((lc)->ptr_value)
+#define lfirst_int(lc)			((lc)->int_value)
+#define lfirst_oid(lc)			((lc)->oid_value)
+#define lfirst_node(type,lc)	castNode(type, lfirst(lc))
+
+#define linitial(l)				lfirst(list_head(l))
+#define linitial_int(l)			lfirst_int(list_head(l))
+#define linitial_oid(l)			lfirst_oid(list_head(l))
+#define linitial_node(type,l)	castNode(type, linitial(l))
+
+#define lsecond(l)				lfirst(list_second_cell(l))
+#define lsecond_int(l)			lfirst_int(list_second_cell(l))
+#define lsecond_oid(l)			lfirst_oid(list_second_cell(l))
+#define lsecond_node(type,l)	castNode(type, lsecond(l))
+
+#define lthird(l)				lfirst(list_third_cell(l))
+#define lthird_int(l)			lfirst_int(list_third_cell(l))
+#define lthird_oid(l)			lfirst_oid(list_third_cell(l))
+#define lthird_node(type,l)		castNode(type, lthird(l))
+
+#define lfourth(l)				lfirst(list_fourth_cell(l))
+#define lfourth_int(l)			lfirst_int(list_fourth_cell(l))
+#define lfourth_oid(l)			lfirst_oid(list_fourth_cell(l))
+#define lfourth_node(type,l)	castNode(type, lfourth(l))
+
+#define llast(l)				lfirst(list_tail(l))
+#define llast_int(l)			lfirst_int(list_tail(l))
+#define llast_oid(l)			lfirst_oid(list_tail(l))
+#define llast_node(type,l)		castNode(type, llast(l))
+
+/*
+ * Convenience macros for building fixed-length lists
+ */
+#define list_make_ptr_cell(v)	((ListCell) {.ptr_value = (v)})
+#define list_make_int_cell(v)	((ListCell) {.int_value = (v)})
+#define list_make_oid_cell(v)	((ListCell) {.oid_value = (v)})
+
+#define list_make1(x1) \
+	list_make1_impl(T_List, list_make_ptr_cell(x1))
+#define list_make2(x1,x2) \
+	list_make2_impl(T_List, list_make_ptr_cell(x1), list_make_ptr_cell(x2))
+#define list_make3(x1,x2,x3) \
+	list_make3_impl(T_List, list_make_ptr_cell(x1), list_make_ptr_cell(x2), \
+					list_make_ptr_cell(x3))
+#define list_make4(x1,x2,x3,x4) \
+	list_make4_impl(T_List, list_make_ptr_cell(x1), list_make_ptr_cell(x2), \
+					list_make_ptr_cell(x3), list_make_ptr_cell(x4))
+
+#define list_make1_int(x1) \
+	list_make1_impl(T_IntList, list_make_int_cell(x1))
+#define list_make2_int(x1,x2) \
+	list_make2_impl(T_IntList, list_make_int_cell(x1), list_make_int_cell(x2))
+#define list_make3_int(x1,x2,x3) \
+	list_make3_impl(T_IntList, list_make_int_cell(x1), list_make_int_cell(x2), \
+					list_make_int_cell(x3))
+#define list_make4_int(x1,x2,x3,x4) \
+	list_make4_impl(T_IntList, list_make_int_cell(x1), list_make_int_cell(x2), \
+					list_make_int_cell(x3), list_make_int_cell(x4))
+
+#define list_make1_oid(x1) \
+	list_make1_impl(T_OidList, list_make_oid_cell(x1))
+#define list_make2_oid(x1,x2) \
+	list_make2_impl(T_OidList, list_make_oid_cell(x1), list_make_oid_cell(x2))
+#define list_make3_oid(x1,x2,x3) \
+	list_make3_impl(T_OidList, list_make_oid_cell(x1), list_make_oid_cell(x2), \
+					list_make_oid_cell(x3))
+#define list_make4_oid(x1,x2,x3,x4) \
+	list_make4_impl(T_OidList, list_make_oid_cell(x1), list_make_oid_cell(x2), \
+					list_make_oid_cell(x3), list_make_oid_cell(x4))
+
+/*
+ * Locate the n'th cell (counting from 0) of the list.
+ * It is an assertion failure if there is no such cell.
+ */
+static inline ListCell *
+list_nth_cell(const List *list, int n)
+{
+	Assert(list != NIL);
+	Assert(n >= 0 && n < list->length);
+	return &list->elements[n];
+}
+
+/*
+ * Return the pointer value contained in the n'th element of the
+ * specified list. (List elements begin at 0.)
+ */
+static inline void *
+list_nth(const List *list, int n)
+{
+	Assert(IsA(list, List));
+	return lfirst(list_nth_cell(list, n));
+}
+
+/*
+ * Return the integer value contained in the n'th element of the
+ * specified list.
+ */
+static inline int
+list_nth_int(const List *list, int n)
+{
+	Assert(IsA(list, IntList));
+	return lfirst_int(list_nth_cell(list, n));
+}
+
+/*
+ * Return the OID value contained in the n'th element of the specified
+ * list.
+ */
+static inline Oid
+list_nth_oid(const List *list, int n)
+{
+	Assert(IsA(list, OidList));
+	return lfirst_oid(list_nth_cell(list, n));
+}
+
+#define list_nth_node(type,list,n)	castNode(type, list_nth(list, n))
+
+/*
+ * Get the given ListCell's index (from 0) in the given List.
+ */
+static inline int
+list_cell_number(const List *l, const ListCell *c)
+{
+	Assert(c >= &l->elements[0] && c < &l->elements[l->length]);
+	return c - l->elements;
+}
+
+/*
+ * Get the address of the next cell after "c" within list "l", or NULL if none.
+ */
+static inline ListCell *
+lnext(const List *l, const ListCell *c)
+{
+	Assert(c >= &l->elements[0] && c < &l->elements[l->length]);
+	c++;
+	if (c < &l->elements[l->length])
+		return (ListCell *) c;
+	else
+		return NULL;
+}
+
+/*
+ * foreach -
+ *	  a convenience macro for looping through a list
+ *
+ * "cell" must be the name of a "ListCell *" variable; it's made to point
+ * to each List element in turn.  "cell" will be NULL after normal exit from
+ * the loop, but an early "break" will leave it pointing at the current
+ * List element.
+ *
+ * Beware of changing the List object while the loop is iterating.
+ * The current semantics are that we examine successive list indices in
+ * each iteration, so that insertion or deletion of list elements could
+ * cause elements to be re-visited or skipped unexpectedly.  Previous
+ * implementations of foreach() behaved differently.  However, it's safe
+ * to append elements to the List (or in general, insert them after the
+ * current element); such new elements are guaranteed to be visited.
+ * Also, the current element of the List can be deleted, if you use
+ * foreach_delete_current() to do so.  BUT: either of these actions will
+ * invalidate the "cell" pointer for the remainder of the current iteration.
+ */
+#define foreach(cell, lst)	\
+	for (ForEachState cell##__state = {(lst), 0}; \
+		 (cell##__state.l != NIL && \
+		  cell##__state.i < cell##__state.l->length) ? \
+		 (cell = &cell##__state.l->elements[cell##__state.i], true) : \
+		 (cell = NULL, false); \
+		 cell##__state.i++)
+
+/*
+ * foreach_delete_current -
+ *	  delete the current list element from the List associated with a
+ *	  surrounding foreach() loop, returning the new List pointer.
+ *
+ * This is equivalent to list_delete_cell(), but it also adjusts the foreach
+ * loop's state so that no list elements will be missed.  Do not delete
+ * elements from an active foreach loop's list in any other way!
+ */
+#define foreach_delete_current(lst, cell)	\
+	(cell##__state.i--, \
+	 (List *) (cell##__state.l = list_delete_cell(lst, cell)))
+
+/*
+ * foreach_current_index -
+ *	  get the zero-based list index of a surrounding foreach() loop's
+ *	  current element; pass the name of the "ListCell *" iterator variable.
+ *
+ * Beware of using this after foreach_delete_current(); the value will be
+ * out of sync for the rest of the current loop iteration.  Anyway, since
+ * you just deleted the current element, the value is pretty meaningless.
+ */
+#define foreach_current_index(cell)  (cell##__state.i)
+
+/*
+ * for_each_from -
+ *	  Like foreach(), but start from the N'th (zero-based) list element,
+ *	  not necessarily the first one.
+ *
+ * It's okay for N to exceed the list length, but not for it to be negative.
+ *
+ * The caveats for foreach() apply equally here.
+ */
+#define for_each_from(cell, lst, N)	\
+	for (ForEachState cell##__state = for_each_from_setup(lst, N); \
+		 (cell##__state.l != NIL && \
+		  cell##__state.i < cell##__state.l->length) ? \
+		 (cell = &cell##__state.l->elements[cell##__state.i], true) : \
+		 (cell = NULL, false); \
+		 cell##__state.i++)
+
+static inline ForEachState
+for_each_from_setup(const List *lst, int N)
+{
+	ForEachState r = {lst, N};
+
+	Assert(N >= 0);
+	return r;
+}
+
+/*
+ * for_each_cell -
+ *	  a convenience macro which loops through a list starting from a
+ *	  specified cell
+ *
+ * The caveats for foreach() apply equally here.
+ */
+#define for_each_cell(cell, lst, initcell)	\
+	for (ForEachState cell##__state = for_each_cell_setup(lst, initcell); \
+		 (cell##__state.l != NIL && \
+		  cell##__state.i < cell##__state.l->length) ? \
+		 (cell = &cell##__state.l->elements[cell##__state.i], true) : \
+		 (cell = NULL, false); \
+		 cell##__state.i++)
+
+static inline ForEachState
+for_each_cell_setup(const List *lst, const ListCell *initcell)
+{
+	ForEachState r = {lst,
+	initcell ? list_cell_number(lst, initcell) : list_length(lst)};
+
+	return r;
+}
+
+/*
+ * forboth -
+ *	  a convenience macro for advancing through two linked lists
+ *	  simultaneously. This macro loops through both lists at the same
+ *	  time, stopping when either list runs out of elements. Depending
+ *	  on the requirements of the call site, it may also be wise to
+ *	  assert that the lengths of the two lists are equal. (But, if they
+ *	  are not, some callers rely on the ending cell values being separately
+ *	  NULL or non-NULL as defined here; don't try to optimize that.)
+ *
+ * The caveats for foreach() apply equally here.
+ */
+#define forboth(cell1, list1, cell2, list2)							\
+	for (ForBothState cell1##__state = {(list1), (list2), 0}; \
+		 multi_for_advance_cell(cell1, cell1##__state, l1, i), \
+		 multi_for_advance_cell(cell2, cell1##__state, l2, i), \
+		 (cell1 != NULL && cell2 != NULL); \
+		 cell1##__state.i++)
+
+#define multi_for_advance_cell(cell, state, l, i) \
+	(cell = (state.l != NIL && state.i < state.l->length) ? \
+	 &state.l->elements[state.i] : NULL)
+
+/*
+ * for_both_cell -
+ *	  a convenience macro which loops through two lists starting from the
+ *	  specified cells of each. This macro loops through both lists at the same
+ *	  time, stopping when either list runs out of elements.  Depending on the
+ *	  requirements of the call site, it may also be wise to assert that the
+ *	  lengths of the two lists are equal, and initcell1 and initcell2 are at
+ *	  the same position in the respective lists.
+ *
+ * The caveats for foreach() apply equally here.
+ */
+#define for_both_cell(cell1, list1, initcell1, cell2, list2, initcell2)	\
+	for (ForBothCellState cell1##__state = \
+			 for_both_cell_setup(list1, initcell1, list2, initcell2); \
+		 multi_for_advance_cell(cell1, cell1##__state, l1, i1), \
+		 multi_for_advance_cell(cell2, cell1##__state, l2, i2), \
+		 (cell1 != NULL && cell2 != NULL); \
+		 cell1##__state.i1++, cell1##__state.i2++)
+
+static inline ForBothCellState
+for_both_cell_setup(const List *list1, const ListCell *initcell1,
+					const List *list2, const ListCell *initcell2)
+{
+	ForBothCellState r = {list1, list2,
+		initcell1 ? list_cell_number(list1, initcell1) : list_length(list1),
+	initcell2 ? list_cell_number(list2, initcell2) : list_length(list2)};
+
+	return r;
+}
+
+/*
+ * forthree -
+ *	  the same for three lists
+ */
+#define forthree(cell1, list1, cell2, list2, cell3, list3) \
+	for (ForThreeState cell1##__state = {(list1), (list2), (list3), 0}; \
+		 multi_for_advance_cell(cell1, cell1##__state, l1, i), \
+		 multi_for_advance_cell(cell2, cell1##__state, l2, i), \
+		 multi_for_advance_cell(cell3, cell1##__state, l3, i), \
+		 (cell1 != NULL && cell2 != NULL && cell3 != NULL); \
+		 cell1##__state.i++)
+
+/*
+ * forfour -
+ *	  the same for four lists
+ */
+#define forfour(cell1, list1, cell2, list2, cell3, list3, cell4, list4) \
+	for (ForFourState cell1##__state = {(list1), (list2), (list3), (list4), 0}; \
+		 multi_for_advance_cell(cell1, cell1##__state, l1, i), \
+		 multi_for_advance_cell(cell2, cell1##__state, l2, i), \
+		 multi_for_advance_cell(cell3, cell1##__state, l3, i), \
+		 multi_for_advance_cell(cell4, cell1##__state, l4, i), \
+		 (cell1 != NULL && cell2 != NULL && cell3 != NULL && cell4 != NULL); \
+		 cell1##__state.i++)
+
+/*
+ * forfive -
+ *	  the same for five lists
+ */
+#define forfive(cell1, list1, cell2, list2, cell3, list3, cell4, list4, cell5, list5) \
+	for (ForFiveState cell1##__state = {(list1), (list2), (list3), (list4), (list5), 0}; \
+		 multi_for_advance_cell(cell1, cell1##__state, l1, i), \
+		 multi_for_advance_cell(cell2, cell1##__state, l2, i), \
+		 multi_for_advance_cell(cell3, cell1##__state, l3, i), \
+		 multi_for_advance_cell(cell4, cell1##__state, l4, i), \
+		 multi_for_advance_cell(cell5, cell1##__state, l5, i), \
+		 (cell1 != NULL && cell2 != NULL && cell3 != NULL && \
+		  cell4 != NULL && cell5 != NULL); \
+		 cell1##__state.i++)
+
+/* Functions in src/backend/nodes/list.c */
+
+extern List *list_make1_impl(NodeTag t, ListCell datum1);
+extern List *list_make2_impl(NodeTag t, ListCell datum1, ListCell datum2);
+extern List *list_make3_impl(NodeTag t, ListCell datum1, ListCell datum2,
+							 ListCell datum3);
+extern List *list_make4_impl(NodeTag t, ListCell datum1, ListCell datum2,
+							 ListCell datum3, ListCell datum4);
+
+extern List *lappend(List *list, void *datum);
+extern List *lappend_int(List *list, int datum);
+extern List *lappend_oid(List *list, Oid datum);
+
+extern List *list_insert_nth(List *list, int pos, void *datum);
+extern List *list_insert_nth_int(List *list, int pos, int datum);
+extern List *list_insert_nth_oid(List *list, int pos, Oid datum);
+
+extern List *lcons(void *datum, List *list);
+extern List *lcons_int(int datum, List *list);
+extern List *lcons_oid(Oid datum, List *list);
+
+extern List *list_concat(List *list1, const List *list2);
+extern List *list_concat_copy(const List *list1, const List *list2);
+
+extern List *list_truncate(List *list, int new_size);
+
+extern bool list_member(const List *list, const void *datum);
+extern bool list_member_ptr(const List *list, const void *datum);
+extern bool list_member_int(const List *list, int datum);
+extern bool list_member_oid(const List *list, Oid datum);
+
+extern List *list_delete(List *list, void *datum);
+extern List *list_delete_ptr(List *list, void *datum);
+extern List *list_delete_int(List *list, int datum);
+extern List *list_delete_oid(List *list, Oid datum);
+extern List *list_delete_first(List *list);
+extern List *list_delete_last(List *list);
+extern List *list_delete_nth_cell(List *list, int n);
+extern List *list_delete_cell(List *list, ListCell *cell);
+
+extern List *list_union(const List *list1, const List *list2);
+extern List *list_union_ptr(const List *list1, const List *list2);
+extern List *list_union_int(const List *list1, const List *list2);
+extern List *list_union_oid(const List *list1, const List *list2);
+
+extern List *list_intersection(const List *list1, const List *list2);
+extern List *list_intersection_int(const List *list1, const List *list2);
+
+/* currently, there's no need for list_intersection_ptr etc */
+
+extern List *list_difference(const List *list1, const List *list2);
+extern List *list_difference_ptr(const List *list1, const List *list2);
+extern List *list_difference_int(const List *list1, const List *list2);
+extern List *list_difference_oid(const List *list1, const List *list2);
+
+extern List *list_append_unique(List *list, void *datum);
+extern List *list_append_unique_ptr(List *list, void *datum);
+extern List *list_append_unique_int(List *list, int datum);
+extern List *list_append_unique_oid(List *list, Oid datum);
+
+extern List *list_concat_unique(List *list1, const List *list2);
+extern List *list_concat_unique_ptr(List *list1, const List *list2);
+extern List *list_concat_unique_int(List *list1, const List *list2);
+extern List *list_concat_unique_oid(List *list1, const List *list2);
+
+extern void list_deduplicate_oid(List *list);
+
+extern void list_free(List *list);
+extern void list_free_deep(List *list);
+
+extern List *list_copy(const List *list);
+extern List *list_copy_tail(const List *list, int nskip);
+extern List *list_copy_deep(const List *oldlist);
+
+typedef int (*list_sort_comparator) (const ListCell *a, const ListCell *b);
+extern void list_sort(List *list, list_sort_comparator cmp);
+
+extern int	list_oid_cmp(const ListCell *p1, const ListCell *p2);
+
+#endif							/* PG_LIST_H */
diff --git a/src/include/nodes/plannodes.h b/src/include/nodes/plannodes.h
new file mode 100644
index 0000000..83e0107
--- /dev/null
+++ b/src/include/nodes/plannodes.h
@@ -0,0 +1,1251 @@
+/*-------------------------------------------------------------------------
+ *
+ * plannodes.h
+ *	  definitions for query plan nodes
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/plannodes.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef PLANNODES_H
+#define PLANNODES_H
+
+#include "access/sdir.h"
+#include "access/stratnum.h"
+#include "lib/stringinfo.h"
+#include "nodes/bitmapset.h"
+#include "nodes/lockoptions.h"
+#include "nodes/primnodes.h"
+
+
+/* ----------------------------------------------------------------
+ *						node definitions
+ * ----------------------------------------------------------------
+ */
+
+/* ----------------
+ *		PlannedStmt node
+ *
+ * The output of the planner is a Plan tree headed by a PlannedStmt node.
+ * PlannedStmt holds the "one time" information needed by the executor.
+ *
+ * For simplicity in APIs, we also wrap utility statements in PlannedStmt
+ * nodes; in such cases, commandType == CMD_UTILITY, the statement itself
+ * is in the utilityStmt field, and the rest of the struct is mostly dummy.
+ * (We do use canSetTag, stmt_location, stmt_len, and possibly queryId.)
+ * ----------------
+ */
+typedef struct PlannedStmt
+{
+	NodeTag		type;
+
+	CmdType		commandType;	/* select|insert|update|delete|utility */
+
+	uint64		queryId;		/* query identifier (copied from Query) */
+
+	bool		hasReturning;	/* is it insert|update|delete RETURNING? */
+
+	bool		hasModifyingCTE;	/* has insert|update|delete in WITH? */
+
+	bool		canSetTag;		/* do I set the command result tag? */
+
+	bool		transientPlan;	/* redo plan when TransactionXmin changes? */
+
+	bool		dependsOnRole;	/* is plan specific to current role? */
+
+	bool		parallelModeNeeded; /* parallel mode required to execute? */
+
+	int			jitFlags;		/* which forms of JIT should be performed */
+
+	struct Plan *planTree;		/* tree of Plan nodes */
+
+	List	   *rtable;			/* list of RangeTblEntry nodes */
+
+	/* rtable indexes of target relations for INSERT/UPDATE/DELETE */
+	List	   *resultRelations;	/* integer list of RT indexes, or NIL */
+
+	/*
+	 * rtable indexes of partitioned table roots that are UPDATE/DELETE
+	 * targets; needed for trigger firing.
+	 */
+	List	   *rootResultRelations;
+
+	List	   *appendRelations;	/* list of AppendRelInfo nodes */
+
+	List	   *subplans;		/* Plan trees for SubPlan expressions; note
+								 * that some could be NULL */
+
+	Bitmapset  *rewindPlanIDs;	/* indices of subplans that require REWIND */
+
+	List	   *rowMarks;		/* a list of PlanRowMark's */
+
+	List	   *relationOids;	/* OIDs of relations the plan depends on */
+
+	List	   *invalItems;		/* other dependencies, as PlanInvalItems */
+
+	List	   *paramExecTypes; /* type OIDs for PARAM_EXEC Params */
+
+	Node	   *utilityStmt;	/* non-null if this is utility stmt */
+
+	/* statement location in source string (copied from Query) */
+	int			stmt_location;	/* start location, or -1 if unknown */
+	int			stmt_len;		/* length in bytes; 0 means "rest of string" */
+} PlannedStmt;
+
+/* macro for fetching the Plan associated with a SubPlan node */
+#define exec_subplan_get_plan(plannedstmt, subplan) \
+	((Plan *) list_nth((plannedstmt)->subplans, (subplan)->plan_id - 1))
+
+
+/* ----------------
+ *		Plan node
+ *
+ * All plan nodes "derive" from the Plan structure by having the
+ * Plan structure as the first field.  This ensures that everything works
+ * when nodes are cast to Plan's.  (node pointers are frequently cast to Plan*
+ * when passed around generically in the executor)
+ *
+ * We never actually instantiate any Plan nodes; this is just the common
+ * abstract superclass for all Plan-type nodes.
+ * ----------------
+ */
+typedef struct Plan
+{
+	NodeTag		type;
+
+	/*
+	 * estimated execution costs for plan (see costsize.c for more info)
+	 */
+	Cost		startup_cost;	/* cost expended before fetching any tuples */
+	Cost		total_cost;		/* total cost (assuming all tuples fetched) */
+
+	/*
+	 * planner's estimate of result size of this plan step
+	 */
+	double		plan_rows;		/* number of rows plan is expected to emit */
+	int			plan_width;		/* average row width in bytes */
+
+	/*
+	 * information needed for parallel query
+	 */
+	bool		parallel_aware; /* engage parallel-aware logic? */
+	bool		parallel_safe;	/* OK to use as part of parallel plan? */
+
+	/*
+	 * Common structural data for all Plan types.
+	 */
+	int			plan_node_id;	/* unique across entire final plan tree */
+	List	   *targetlist;		/* target list to be computed at this node */
+	List	   *qual;			/* implicitly-ANDed qual conditions */
+	struct Plan *lefttree;		/* input plan tree(s) */
+	struct Plan *righttree;
+	List	   *initPlan;		/* Init Plan nodes (un-correlated expr
+								 * subselects) */
+
+	/*
+	 * Information for management of parameter-change-driven rescanning
+	 *
+	 * extParam includes the paramIDs of all external PARAM_EXEC params
+	 * affecting this plan node or its children.  setParam params from the
+	 * node's initPlans are not included, but their extParams are.
+	 *
+	 * allParam includes all the extParam paramIDs, plus the IDs of local
+	 * params that affect the node (i.e., the setParams of its initplans).
+	 * These are _all_ the PARAM_EXEC params that affect this node.
+	 */
+	Bitmapset  *extParam;
+	Bitmapset  *allParam;
+} Plan;
+
+/* ----------------
+ *	these are defined to avoid confusion problems with "left"
+ *	and "right" and "inner" and "outer".  The convention is that
+ *	the "left" plan is the "outer" plan and the "right" plan is
+ *	the inner plan, but these make the code more readable.
+ * ----------------
+ */
+#define innerPlan(node)			(((Plan *)(node))->righttree)
+#define outerPlan(node)			(((Plan *)(node))->lefttree)
+
+
+/* ----------------
+ *	 Result node -
+ *		If no outer plan, evaluate a variable-free targetlist.
+ *		If outer plan, return tuples from outer plan (after a level of
+ *		projection as shown by targetlist).
+ *
+ * If resconstantqual isn't NULL, it represents a one-time qualification
+ * test (i.e., one that doesn't depend on any variables from the outer plan,
+ * so needs to be evaluated only once).
+ * ----------------
+ */
+typedef struct Result
+{
+	Plan		plan;
+	Node	   *resconstantqual;
+} Result;
+
+/* ----------------
+ *	 ProjectSet node -
+ *		Apply a projection that includes set-returning functions to the
+ *		output tuples of the outer plan.
+ * ----------------
+ */
+typedef struct ProjectSet
+{
+	Plan		plan;
+} ProjectSet;
+
+/* ----------------
+ *	 ModifyTable node -
+ *		Apply rows produced by subplan(s) to result table(s),
+ *		by inserting, updating, or deleting.
+ *
+ * If the originally named target table is a partitioned table, both
+ * nominalRelation and rootRelation contain the RT index of the partition
+ * root, which is not otherwise mentioned in the plan.  Otherwise rootRelation
+ * is zero.  However, nominalRelation will always be set, as it's the rel that
+ * EXPLAIN should claim is the INSERT/UPDATE/DELETE target.
+ *
+ * Note that rowMarks and epqParam are presumed to be valid for all the
+ * subplan(s); they can't contain any info that varies across subplans.
+ * ----------------
+ */
+typedef struct ModifyTable
+{
+	Plan		plan;
+	CmdType		operation;		/* INSERT, UPDATE, or DELETE */
+	bool		canSetTag;		/* do we set the command tag/es_processed? */
+	Index		nominalRelation;	/* Parent RT index for use of EXPLAIN */
+	Index		rootRelation;	/* Root RT index, if target is partitioned */
+	bool		partColsUpdated;	/* some part key in hierarchy updated */
+	List	   *resultRelations;	/* integer list of RT indexes */
+	int			resultRelIndex; /* index of first resultRel in plan's list */
+	int			rootResultRelIndex; /* index of the partitioned table root */
+	List	   *plans;			/* plan(s) producing source data */
+	List	   *withCheckOptionLists;	/* per-target-table WCO lists */
+	List	   *returningLists; /* per-target-table RETURNING tlists */
+	List	   *fdwPrivLists;	/* per-target-table FDW private data lists */
+	Bitmapset  *fdwDirectModifyPlans;	/* indices of FDW DM plans */
+	List	   *rowMarks;		/* PlanRowMarks (non-locking only) */
+	int			epqParam;		/* ID of Param for EvalPlanQual re-eval */
+	OnConflictAction onConflictAction;	/* ON CONFLICT action */
+	List	   *arbiterIndexes; /* List of ON CONFLICT arbiter index OIDs  */
+	List	   *onConflictSet;	/* SET for INSERT ON CONFLICT DO UPDATE */
+	Node	   *onConflictWhere;	/* WHERE for ON CONFLICT UPDATE */
+	Index		exclRelRTI;		/* RTI of the EXCLUDED pseudo relation */
+	List	   *exclRelTlist;	/* tlist of the EXCLUDED pseudo relation */
+} ModifyTable;
+
+struct PartitionPruneInfo;		/* forward reference to struct below */
+
+/* ----------------
+ *	 Append node -
+ *		Generate the concatenation of the results of sub-plans.
+ * ----------------
+ */
+typedef struct Append
+{
+	Plan		plan;
+	Bitmapset  *apprelids;		/* RTIs of appendrel(s) formed by this node */
+	List	   *appendplans;
+
+	/*
+	 * All 'appendplans' preceding this index are non-partial plans. All
+	 * 'appendplans' from this index onwards are partial plans.
+	 */
+	int			first_partial_plan;
+
+	/* Info for run-time subplan pruning; NULL if we're not doing that */
+	struct PartitionPruneInfo *part_prune_info;
+} Append;
+
+/* ----------------
+ *	 MergeAppend node -
+ *		Merge the results of pre-sorted sub-plans to preserve the ordering.
+ * ----------------
+ */
+typedef struct MergeAppend
+{
+	Plan		plan;
+	Bitmapset  *apprelids;		/* RTIs of appendrel(s) formed by this node */
+	List	   *mergeplans;
+	/* these fields are just like the sort-key info in struct Sort: */
+	int			numCols;		/* number of sort-key columns */
+	AttrNumber *sortColIdx;		/* their indexes in the target list */
+	Oid		   *sortOperators;	/* OIDs of operators to sort them by */
+	Oid		   *collations;		/* OIDs of collations */
+	bool	   *nullsFirst;		/* NULLS FIRST/LAST directions */
+	/* Info for run-time subplan pruning; NULL if we're not doing that */
+	struct PartitionPruneInfo *part_prune_info;
+} MergeAppend;
+
+/* ----------------
+ *	RecursiveUnion node -
+ *		Generate a recursive union of two subplans.
+ *
+ * The "outer" subplan is always the non-recursive term, and the "inner"
+ * subplan is the recursive term.
+ * ----------------
+ */
+typedef struct RecursiveUnion
+{
+	Plan		plan;
+	int			wtParam;		/* ID of Param representing work table */
+	/* Remaining fields are zero/null in UNION ALL case */
+	int			numCols;		/* number of columns to check for
+								 * duplicate-ness */
+	AttrNumber *dupColIdx;		/* their indexes in the target list */
+	Oid		   *dupOperators;	/* equality operators to compare with */
+	Oid		   *dupCollations;
+	long		numGroups;		/* estimated number of groups in input */
+} RecursiveUnion;
+
+/* ----------------
+ *	 BitmapAnd node -
+ *		Generate the intersection of the results of sub-plans.
+ *
+ * The subplans must be of types that yield tuple bitmaps.  The targetlist
+ * and qual fields of the plan are unused and are always NIL.
+ * ----------------
+ */
+typedef struct BitmapAnd
+{
+	Plan		plan;
+	List	   *bitmapplans;
+} BitmapAnd;
+
+/* ----------------
+ *	 BitmapOr node -
+ *		Generate the union of the results of sub-plans.
+ *
+ * The subplans must be of types that yield tuple bitmaps.  The targetlist
+ * and qual fields of the plan are unused and are always NIL.
+ * ----------------
+ */
+typedef struct BitmapOr
+{
+	Plan		plan;
+	bool		isshared;
+	List	   *bitmapplans;
+} BitmapOr;
+
+/*
+ * ==========
+ * Scan nodes
+ * ==========
+ */
+typedef struct Scan
+{
+	Plan		plan;
+	Index		scanrelid;		/* relid is index into the range table */
+} Scan;
+
+/* ----------------
+ *		sequential scan node
+ * ----------------
+ */
+typedef Scan SeqScan;
+
+/* ----------------
+ *		table sample scan node
+ * ----------------
+ */
+typedef struct SampleScan
+{
+	Scan		scan;
+	/* use struct pointer to avoid including parsenodes.h here */
+	struct TableSampleClause *tablesample;
+} SampleScan;
+
+/* ----------------
+ *		index scan node
+ *
+ * indexqualorig is an implicitly-ANDed list of index qual expressions, each
+ * in the same form it appeared in the query WHERE condition.  Each should
+ * be of the form (indexkey OP comparisonval) or (comparisonval OP indexkey).
+ * The indexkey is a Var or expression referencing column(s) of the index's
+ * base table.  The comparisonval might be any expression, but it won't use
+ * any columns of the base table.  The expressions are ordered by index
+ * column position (but items referencing the same index column can appear
+ * in any order).  indexqualorig is used at runtime only if we have to recheck
+ * a lossy indexqual.
+ *
+ * indexqual has the same form, but the expressions have been commuted if
+ * necessary to put the indexkeys on the left, and the indexkeys are replaced
+ * by Var nodes identifying the index columns (their varno is INDEX_VAR and
+ * their varattno is the index column number).
+ *
+ * indexorderbyorig is similarly the original form of any ORDER BY expressions
+ * that are being implemented by the index, while indexorderby is modified to
+ * have index column Vars on the left-hand side.  Here, multiple expressions
+ * must appear in exactly the ORDER BY order, and this is not necessarily the
+ * index column order.  Only the expressions are provided, not the auxiliary
+ * sort-order information from the ORDER BY SortGroupClauses; it's assumed
+ * that the sort ordering is fully determinable from the top-level operators.
+ * indexorderbyorig is used at runtime to recheck the ordering, if the index
+ * cannot calculate an accurate ordering.  It is also needed for EXPLAIN.
+ *
+ * indexorderbyops is a list of the OIDs of the operators used to sort the
+ * ORDER BY expressions.  This is used together with indexorderbyorig to
+ * recheck ordering at run time.  (Note that indexorderby, indexorderbyorig,
+ * and indexorderbyops are used for amcanorderbyop cases, not amcanorder.)
+ *
+ * indexorderdir specifies the scan ordering, for indexscans on amcanorder
+ * indexes (for other indexes it should be "don't care").
+ * ----------------
+ */
+typedef struct IndexScan
+{
+	Scan		scan;
+	Oid			indexid;		/* OID of index to scan */
+	List	   *indexqual;		/* list of index quals (usually OpExprs) */
+	List	   *indexqualorig;	/* the same in original form */
+	List	   *indexorderby;	/* list of index ORDER BY exprs */
+	List	   *indexorderbyorig;	/* the same in original form */
+	List	   *indexorderbyops;	/* OIDs of sort ops for ORDER BY exprs */
+	ScanDirection indexorderdir;	/* forward or backward or don't care */
+} IndexScan;
+
+/* ----------------
+ *		index-only scan node
+ *
+ * IndexOnlyScan is very similar to IndexScan, but it specifies an
+ * index-only scan, in which the data comes from the index not the heap.
+ * Because of this, *all* Vars in the plan node's targetlist, qual, and
+ * index expressions reference index columns and have varno = INDEX_VAR.
+ * Hence we do not need separate indexqualorig and indexorderbyorig lists,
+ * since their contents would be equivalent to indexqual and indexorderby.
+ *
+ * To help EXPLAIN interpret the index Vars for display, we provide
+ * indextlist, which represents the contents of the index as a targetlist
+ * with one TLE per index column.  Vars appearing in this list reference
+ * the base table, and this is the only field in the plan node that may
+ * contain such Vars.
+ * ----------------
+ */
+typedef struct IndexOnlyScan
+{
+	Scan		scan;
+	Oid			indexid;		/* OID of index to scan */
+	List	   *indexqual;		/* list of index quals (usually OpExprs) */
+	List	   *indexorderby;	/* list of index ORDER BY exprs */
+	List	   *indextlist;		/* TargetEntry list describing index's cols */
+	ScanDirection indexorderdir;	/* forward or backward or don't care */
+} IndexOnlyScan;
+
+/* ----------------
+ *		bitmap index scan node
+ *
+ * BitmapIndexScan delivers a bitmap of potential tuple locations;
+ * it does not access the heap itself.  The bitmap is used by an
+ * ancestor BitmapHeapScan node, possibly after passing through
+ * intermediate BitmapAnd and/or BitmapOr nodes to combine it with
+ * the results of other BitmapIndexScans.
+ *
+ * The fields have the same meanings as for IndexScan, except we don't
+ * store a direction flag because direction is uninteresting.
+ *
+ * In a BitmapIndexScan plan node, the targetlist and qual fields are
+ * not used and are always NIL.  The indexqualorig field is unused at
+ * run time too, but is saved for the benefit of EXPLAIN.
+ * ----------------
+ */
+typedef struct BitmapIndexScan
+{
+	Scan		scan;
+	Oid			indexid;		/* OID of index to scan */
+	bool		isshared;		/* Create shared bitmap if set */
+	List	   *indexqual;		/* list of index quals (OpExprs) */
+	List	   *indexqualorig;	/* the same in original form */
+} BitmapIndexScan;
+
+/* ----------------
+ *		bitmap sequential scan node
+ *
+ * This needs a copy of the qual conditions being used by the input index
+ * scans because there are various cases where we need to recheck the quals;
+ * for example, when the bitmap is lossy about the specific rows on a page
+ * that meet the index condition.
+ * ----------------
+ */
+typedef struct BitmapHeapScan
+{
+	Scan		scan;
+	List	   *bitmapqualorig; /* index quals, in standard expr form */
+} BitmapHeapScan;
+
+/* ----------------
+ *		tid scan node
+ *
+ * tidquals is an implicitly OR'ed list of qual expressions of the form
+ * "CTID = pseudoconstant", or "CTID = ANY(pseudoconstant_array)",
+ * or a CurrentOfExpr for the relation.
+ * ----------------
+ */
+typedef struct TidScan
+{
+	Scan		scan;
+	List	   *tidquals;		/* qual(s) involving CTID = something */
+} TidScan;
+
+/* ----------------
+ *		subquery scan node
+ *
+ * SubqueryScan is for scanning the output of a sub-query in the range table.
+ * We often need an extra plan node above the sub-query's plan to perform
+ * expression evaluations (which we can't push into the sub-query without
+ * risking changing its semantics).  Although we are not scanning a physical
+ * relation, we make this a descendant of Scan anyway for code-sharing
+ * purposes.
+ *
+ * Note: we store the sub-plan in the type-specific subplan field, not in
+ * the generic lefttree field as you might expect.  This is because we do
+ * not want plan-tree-traversal routines to recurse into the subplan without
+ * knowing that they are changing Query contexts.
+ * ----------------
+ */
+typedef struct SubqueryScan
+{
+	Scan		scan;
+	Plan	   *subplan;
+} SubqueryScan;
+
+/* ----------------
+ *		FunctionScan node
+ * ----------------
+ */
+typedef struct FunctionScan
+{
+	Scan		scan;
+	List	   *functions;		/* list of RangeTblFunction nodes */
+	bool		funcordinality; /* WITH ORDINALITY */
+} FunctionScan;
+
+/* ----------------
+ *		ValuesScan node
+ * ----------------
+ */
+typedef struct ValuesScan
+{
+	Scan		scan;
+	List	   *values_lists;	/* list of expression lists */
+} ValuesScan;
+
+/* ----------------
+ *		TableFunc scan node
+ * ----------------
+ */
+typedef struct TableFuncScan
+{
+	Scan		scan;
+	TableFunc  *tablefunc;		/* table function node */
+} TableFuncScan;
+
+/* ----------------
+ *		CteScan node
+ * ----------------
+ */
+typedef struct CteScan
+{
+	Scan		scan;
+	int			ctePlanId;		/* ID of init SubPlan for CTE */
+	int			cteParam;		/* ID of Param representing CTE output */
+} CteScan;
+
+/* ----------------
+ *		NamedTuplestoreScan node
+ * ----------------
+ */
+typedef struct NamedTuplestoreScan
+{
+	Scan		scan;
+	char	   *enrname;		/* Name given to Ephemeral Named Relation */
+} NamedTuplestoreScan;
+
+/* ----------------
+ *		WorkTableScan node
+ * ----------------
+ */
+typedef struct WorkTableScan
+{
+	Scan		scan;
+	int			wtParam;		/* ID of Param representing work table */
+} WorkTableScan;
+
+/* ----------------
+ *		ForeignScan node
+ *
+ * fdw_exprs and fdw_private are both under the control of the foreign-data
+ * wrapper, but fdw_exprs is presumed to contain expression trees and will
+ * be post-processed accordingly by the planner; fdw_private won't be.
+ * Note that everything in both lists must be copiable by copyObject().
+ * One way to store an arbitrary blob of bytes is to represent it as a bytea
+ * Const.  Usually, though, you'll be better off choosing a representation
+ * that can be dumped usefully by nodeToString().
+ *
+ * fdw_scan_tlist is a targetlist describing the contents of the scan tuple
+ * returned by the FDW; it can be NIL if the scan tuple matches the declared
+ * rowtype of the foreign table, which is the normal case for a simple foreign
+ * table scan.  (If the plan node represents a foreign join, fdw_scan_tlist
+ * is required since there is no rowtype available from the system catalogs.)
+ * When fdw_scan_tlist is provided, Vars in the node's tlist and quals must
+ * have varno INDEX_VAR, and their varattnos correspond to resnos in the
+ * fdw_scan_tlist (which are also column numbers in the actual scan tuple).
+ * fdw_scan_tlist is never actually executed; it just holds expression trees
+ * describing what is in the scan tuple's columns.
+ *
+ * fdw_recheck_quals should contain any quals which the core system passed to
+ * the FDW but which were not added to scan.plan.qual; that is, it should
+ * contain the quals being checked remotely.  This is needed for correct
+ * behavior during EvalPlanQual rechecks.
+ *
+ * When the plan node represents a foreign join, scan.scanrelid is zero and
+ * fs_relids must be consulted to identify the join relation.  (fs_relids
+ * is valid for simple scans as well, but will always match scan.scanrelid.)
+ * ----------------
+ */
+typedef struct ForeignScan
+{
+	Scan		scan;
+	CmdType		operation;		/* SELECT/INSERT/UPDATE/DELETE */
+	Oid			fs_server;		/* OID of foreign server */
+	List	   *fdw_exprs;		/* expressions that FDW may evaluate */
+	List	   *fdw_private;	/* private data for FDW */
+	List	   *fdw_scan_tlist; /* optional tlist describing scan tuple */
+	List	   *fdw_recheck_quals;	/* original quals not in scan.plan.qual */
+	Bitmapset  *fs_relids;		/* RTIs generated by this scan */
+	bool		fsSystemCol;	/* true if any "system column" is needed */
+} ForeignScan;
+
+/* ----------------
+ *	   CustomScan node
+ *
+ * The comments for ForeignScan's fdw_exprs, fdw_private, fdw_scan_tlist,
+ * and fs_relids fields apply equally to CustomScan's custom_exprs,
+ * custom_private, custom_scan_tlist, and custom_relids fields.  The
+ * convention of setting scan.scanrelid to zero for joins applies as well.
+ *
+ * Note that since Plan trees can be copied, custom scan providers *must*
+ * fit all plan data they need into those fields; embedding CustomScan in
+ * a larger struct will not work.
+ * ----------------
+ */
+struct CustomScanMethods;
+
+typedef struct CustomScan
+{
+	Scan		scan;
+	uint32		flags;			/* mask of CUSTOMPATH_* flags, see
+								 * nodes/extensible.h */
+	List	   *custom_plans;	/* list of Plan nodes, if any */
+	List	   *custom_exprs;	/* expressions that custom code may evaluate */
+	List	   *custom_private; /* private data for custom code */
+	List	   *custom_scan_tlist;	/* optional tlist describing scan tuple */
+	Bitmapset  *custom_relids;	/* RTIs generated by this scan */
+	const struct CustomScanMethods *methods;
+} CustomScan;
+
+/*
+ * ==========
+ * Join nodes
+ * ==========
+ */
+
+/* ----------------
+ *		Join node
+ *
+ * jointype:	rule for joining tuples from left and right subtrees
+ * inner_unique each outer tuple can match to no more than one inner tuple
+ * joinqual:	qual conditions that came from JOIN/ON or JOIN/USING
+ *				(plan.qual contains conditions that came from WHERE)
+ *
+ * When jointype is INNER, joinqual and plan.qual are semantically
+ * interchangeable.  For OUTER jointypes, the two are *not* interchangeable;
+ * only joinqual is used to determine whether a match has been found for
+ * the purpose of deciding whether to generate null-extended tuples.
+ * (But plan.qual is still applied before actually returning a tuple.)
+ * For an outer join, only joinquals are allowed to be used as the merge
+ * or hash condition of a merge or hash join.
+ *
+ * inner_unique is set if the joinquals are such that no more than one inner
+ * tuple could match any given outer tuple.  This allows the executor to
+ * skip searching for additional matches.  (This must be provable from just
+ * the joinquals, ignoring plan.qual, due to where the executor tests it.)
+ * ----------------
+ */
+typedef struct Join
+{
+	Plan		plan;
+	JoinType	jointype;
+	bool		inner_unique;
+	List	   *joinqual;		/* JOIN quals (in addition to plan.qual) */
+} Join;
+
+/* ----------------
+ *		nest loop join node
+ *
+ * The nestParams list identifies any executor Params that must be passed
+ * into execution of the inner subplan carrying values from the current row
+ * of the outer subplan.  Currently we restrict these values to be simple
+ * Vars, but perhaps someday that'd be worth relaxing.  (Note: during plan
+ * creation, the paramval can actually be a PlaceHolderVar expression; but it
+ * must be a Var with varno OUTER_VAR by the time it gets to the executor.)
+ * ----------------
+ */
+typedef struct NestLoop
+{
+	Join		join;
+	List	   *nestParams;		/* list of NestLoopParam nodes */
+} NestLoop;
+
+typedef struct NestLoopParam
+{
+	NodeTag		type;
+	int			paramno;		/* number of the PARAM_EXEC Param to set */
+	Var		   *paramval;		/* outer-relation Var to assign to Param */
+} NestLoopParam;
+
+/* ----------------
+ *		merge join node
+ *
+ * The expected ordering of each mergeable column is described by a btree
+ * opfamily OID, a collation OID, a direction (BTLessStrategyNumber or
+ * BTGreaterStrategyNumber) and a nulls-first flag.  Note that the two sides
+ * of each mergeclause may be of different datatypes, but they are ordered the
+ * same way according to the common opfamily and collation.  The operator in
+ * each mergeclause must be an equality operator of the indicated opfamily.
+ * ----------------
+ */
+typedef struct MergeJoin
+{
+	Join		join;
+	bool		skip_mark_restore;	/* Can we skip mark/restore calls? */
+	List	   *mergeclauses;	/* mergeclauses as expression trees */
+	/* these are arrays, but have the same length as the mergeclauses list: */
+	Oid		   *mergeFamilies;	/* per-clause OIDs of btree opfamilies */
+	Oid		   *mergeCollations;	/* per-clause OIDs of collations */
+	int		   *mergeStrategies;	/* per-clause ordering (ASC or DESC) */
+	bool	   *mergeNullsFirst;	/* per-clause nulls ordering */
+} MergeJoin;
+
+/* ----------------
+ *		hash join node
+ * ----------------
+ */
+typedef struct HashJoin
+{
+	Join		join;
+	List	   *hashclauses;
+	List	   *hashoperators;
+	List	   *hashcollations;
+
+	/*
+	 * List of expressions to be hashed for tuples from the outer plan, to
+	 * perform lookups in the hashtable over the inner plan.
+	 */
+	List	   *hashkeys;
+} HashJoin;
+
+/* ----------------
+ *		materialization node
+ * ----------------
+ */
+typedef struct Material
+{
+	Plan		plan;
+} Material;
+
+/* ----------------
+ *		sort node
+ * ----------------
+ */
+typedef struct Sort
+{
+	Plan		plan;
+	int			numCols;		/* number of sort-key columns */
+	AttrNumber *sortColIdx;		/* their indexes in the target list */
+	Oid		   *sortOperators;	/* OIDs of operators to sort them by */
+	Oid		   *collations;		/* OIDs of collations */
+	bool	   *nullsFirst;		/* NULLS FIRST/LAST directions */
+} Sort;
+
+/* ----------------
+ *		incremental sort node
+ * ----------------
+ */
+typedef struct IncrementalSort
+{
+	Sort		sort;
+	int			nPresortedCols; /* number of presorted columns */
+} IncrementalSort;
+
+/* ---------------
+ *	 group node -
+ *		Used for queries with GROUP BY (but no aggregates) specified.
+ *		The input must be presorted according to the grouping columns.
+ * ---------------
+ */
+typedef struct Group
+{
+	Plan		plan;
+	int			numCols;		/* number of grouping columns */
+	AttrNumber *grpColIdx;		/* their indexes in the target list */
+	Oid		   *grpOperators;	/* equality operators to compare with */
+	Oid		   *grpCollations;
+} Group;
+
+/* ---------------
+ *		aggregate node
+ *
+ * An Agg node implements plain or grouped aggregation.  For grouped
+ * aggregation, we can work with presorted input or unsorted input;
+ * the latter strategy uses an internal hashtable.
+ *
+ * Notice the lack of any direct info about the aggregate functions to be
+ * computed.  They are found by scanning the node's tlist and quals during
+ * executor startup.  (It is possible that there are no aggregate functions;
+ * this could happen if they get optimized away by constant-folding, or if
+ * we are using the Agg node to implement hash-based grouping.)
+ * ---------------
+ */
+typedef struct Agg
+{
+	Plan		plan;
+	AggStrategy aggstrategy;	/* basic strategy, see nodes.h */
+	AggSplit	aggsplit;		/* agg-splitting mode, see nodes.h */
+	int			numCols;		/* number of grouping columns */
+	AttrNumber *grpColIdx;		/* their indexes in the target list */
+	Oid		   *grpOperators;	/* equality operators to compare with */
+	Oid		   *grpCollations;
+	long		numGroups;		/* estimated number of groups in input */
+	uint64		transitionSpace;	/* for pass-by-ref transition data */
+	Bitmapset  *aggParams;		/* IDs of Params used in Aggref inputs */
+	/* Note: planner provides numGroups & aggParams only in HASHED/MIXED case */
+	List	   *groupingSets;	/* grouping sets to use */
+	List	   *chain;			/* chained Agg/Sort nodes */
+} Agg;
+
+/* ----------------
+ *		window aggregate node
+ * ----------------
+ */
+typedef struct WindowAgg
+{
+	Plan		plan;
+	Index		winref;			/* ID referenced by window functions */
+	int			partNumCols;	/* number of columns in partition clause */
+	AttrNumber *partColIdx;		/* their indexes in the target list */
+	Oid		   *partOperators;	/* equality operators for partition columns */
+	Oid		   *partCollations; /* collations for partition columns */
+	int			ordNumCols;		/* number of columns in ordering clause */
+	AttrNumber *ordColIdx;		/* their indexes in the target list */
+	Oid		   *ordOperators;	/* equality operators for ordering columns */
+	Oid		   *ordCollations;	/* collations for ordering columns */
+	int			frameOptions;	/* frame_clause options, see WindowDef */
+	Node	   *startOffset;	/* expression for starting bound, if any */
+	Node	   *endOffset;		/* expression for ending bound, if any */
+	/* these fields are used with RANGE offset PRECEDING/FOLLOWING: */
+	Oid			startInRangeFunc;	/* in_range function for startOffset */
+	Oid			endInRangeFunc; /* in_range function for endOffset */
+	Oid			inRangeColl;	/* collation for in_range tests */
+	bool		inRangeAsc;		/* use ASC sort order for in_range tests? */
+	bool		inRangeNullsFirst;	/* nulls sort first for in_range tests? */
+} WindowAgg;
+
+/* ----------------
+ *		unique node
+ * ----------------
+ */
+typedef struct Unique
+{
+	Plan		plan;
+	int			numCols;		/* number of columns to check for uniqueness */
+	AttrNumber *uniqColIdx;		/* their indexes in the target list */
+	Oid		   *uniqOperators;	/* equality operators to compare with */
+	Oid		   *uniqCollations; /* collations for equality comparisons */
+} Unique;
+
+/* ------------
+ *		gather node
+ *
+ * Note: rescan_param is the ID of a PARAM_EXEC parameter slot.  That slot
+ * will never actually contain a value, but the Gather node must flag it as
+ * having changed whenever it is rescanned.  The child parallel-aware scan
+ * nodes are marked as depending on that parameter, so that the rescan
+ * machinery is aware that their output is likely to change across rescans.
+ * In some cases we don't need a rescan Param, so rescan_param is set to -1.
+ * ------------
+ */
+typedef struct Gather
+{
+	Plan		plan;
+	int			num_workers;	/* planned number of worker processes */
+	int			rescan_param;	/* ID of Param that signals a rescan, or -1 */
+	bool		single_copy;	/* don't execute plan more than once */
+	bool		invisible;		/* suppress EXPLAIN display (for testing)? */
+	Bitmapset  *initParam;		/* param id's of initplans which are referred
+								 * at gather or one of it's child node */
+} Gather;
+
+/* ------------
+ *		gather merge node
+ * ------------
+ */
+typedef struct GatherMerge
+{
+	Plan		plan;
+	int			num_workers;	/* planned number of worker processes */
+	int			rescan_param;	/* ID of Param that signals a rescan, or -1 */
+	/* remaining fields are just like the sort-key info in struct Sort */
+	int			numCols;		/* number of sort-key columns */
+	AttrNumber *sortColIdx;		/* their indexes in the target list */
+	Oid		   *sortOperators;	/* OIDs of operators to sort them by */
+	Oid		   *collations;		/* OIDs of collations */
+	bool	   *nullsFirst;		/* NULLS FIRST/LAST directions */
+	Bitmapset  *initParam;		/* param id's of initplans which are referred
+								 * at gather merge or one of it's child node */
+} GatherMerge;
+
+/* ----------------
+ *		hash build node
+ *
+ * If the executor is supposed to try to apply skew join optimization, then
+ * skewTable/skewColumn/skewInherit identify the outer relation's join key
+ * column, from which the relevant MCV statistics can be fetched.
+ * ----------------
+ */
+typedef struct Hash
+{
+	Plan		plan;
+
+	/*
+	 * List of expressions to be hashed for tuples from Hash's outer plan,
+	 * needed to put them into the hashtable.
+	 */
+	List	   *hashkeys;		/* hash keys for the hashjoin condition */
+	Oid			skewTable;		/* outer join key's table OID, or InvalidOid */
+	AttrNumber	skewColumn;		/* outer join key's column #, or zero */
+	bool		skewInherit;	/* is outer join rel an inheritance tree? */
+	/* all other info is in the parent HashJoin node */
+	double		rows_total;		/* estimate total rows if parallel_aware */
+} Hash;
+
+/* ----------------
+ *		setop node
+ * ----------------
+ */
+typedef struct SetOp
+{
+	Plan		plan;
+	SetOpCmd	cmd;			/* what to do, see nodes.h */
+	SetOpStrategy strategy;		/* how to do it, see nodes.h */
+	int			numCols;		/* number of columns to check for
+								 * duplicate-ness */
+	AttrNumber *dupColIdx;		/* their indexes in the target list */
+	Oid		   *dupOperators;	/* equality operators to compare with */
+	Oid		   *dupCollations;
+	AttrNumber	flagColIdx;		/* where is the flag column, if any */
+	int			firstFlag;		/* flag value for first input relation */
+	long		numGroups;		/* estimated number of groups in input */
+} SetOp;
+
+/* ----------------
+ *		lock-rows node
+ *
+ * rowMarks identifies the rels to be locked by this node; it should be
+ * a subset of the rowMarks listed in the top-level PlannedStmt.
+ * epqParam is a Param that all scan nodes below this one must depend on.
+ * It is used to force re-evaluation of the plan during EvalPlanQual.
+ * ----------------
+ */
+typedef struct LockRows
+{
+	Plan		plan;
+	List	   *rowMarks;		/* a list of PlanRowMark's */
+	int			epqParam;		/* ID of Param for EvalPlanQual re-eval */
+} LockRows;
+
+/* ----------------
+ *		limit node
+ *
+ * Note: as of Postgres 8.2, the offset and count expressions are expected
+ * to yield int8, rather than int4 as before.
+ * ----------------
+ */
+typedef struct Limit
+{
+	Plan		plan;
+	Node	   *limitOffset;	/* OFFSET parameter, or NULL if none */
+	Node	   *limitCount;		/* COUNT parameter, or NULL if none */
+	LimitOption limitOption;	/* limit type */
+	int			uniqNumCols;	/* number of columns to check for similarity  */
+	AttrNumber *uniqColIdx;		/* their indexes in the target list */
+	Oid		   *uniqOperators;	/* equality operators to compare with */
+	Oid		   *uniqCollations; /* collations for equality comparisons */
+} Limit;
+
+
+/*
+ * RowMarkType -
+ *	  enums for types of row-marking operations
+ *
+ * The first four of these values represent different lock strengths that
+ * we can take on tuples according to SELECT FOR [KEY] UPDATE/SHARE requests.
+ * We support these on regular tables, as well as on foreign tables whose FDWs
+ * report support for late locking.  For other foreign tables, any locking
+ * that might be done for such requests must happen during the initial row
+ * fetch; their FDWs provide no mechanism for going back to lock a row later.
+ * This means that the semantics will be a bit different than for a local
+ * table; in particular we are likely to lock more rows than would be locked
+ * locally, since remote rows will be locked even if they then fail
+ * locally-checked restriction or join quals.  However, the prospect of
+ * doing a separate remote query to lock each selected row is usually pretty
+ * unappealing, so early locking remains a credible design choice for FDWs.
+ *
+ * When doing UPDATE, DELETE, or SELECT FOR UPDATE/SHARE, we have to uniquely
+ * identify all the source rows, not only those from the target relations, so
+ * that we can perform EvalPlanQual rechecking at need.  For plain tables we
+ * can just fetch the TID, much as for a target relation; this case is
+ * represented by ROW_MARK_REFERENCE.  Otherwise (for example for VALUES or
+ * FUNCTION scans) we have to copy the whole row value.  ROW_MARK_COPY is
+ * pretty inefficient, since most of the time we'll never need the data; but
+ * fortunately the overhead is usually not performance-critical in practice.
+ * By default we use ROW_MARK_COPY for foreign tables, but if the FDW has
+ * a concept of rowid it can request to use ROW_MARK_REFERENCE instead.
+ * (Again, this probably doesn't make sense if a physical remote fetch is
+ * needed, but for FDWs that map to local storage it might be credible.)
+ */
+typedef enum RowMarkType
+{
+	ROW_MARK_EXCLUSIVE,			/* obtain exclusive tuple lock */
+	ROW_MARK_NOKEYEXCLUSIVE,	/* obtain no-key exclusive tuple lock */
+	ROW_MARK_SHARE,				/* obtain shared tuple lock */
+	ROW_MARK_KEYSHARE,			/* obtain keyshare tuple lock */
+	ROW_MARK_REFERENCE,			/* just fetch the TID, don't lock it */
+	ROW_MARK_COPY				/* physically copy the row value */
+} RowMarkType;
+
+#define RowMarkRequiresRowShareLock(marktype)  ((marktype) <= ROW_MARK_KEYSHARE)
+
+/*
+ * PlanRowMark -
+ *	   plan-time representation of FOR [KEY] UPDATE/SHARE clauses
+ *
+ * When doing UPDATE, DELETE, or SELECT FOR UPDATE/SHARE, we create a separate
+ * PlanRowMark node for each non-target relation in the query.  Relations that
+ * are not specified as FOR UPDATE/SHARE are marked ROW_MARK_REFERENCE (if
+ * regular tables or supported foreign tables) or ROW_MARK_COPY (if not).
+ *
+ * Initially all PlanRowMarks have rti == prti and isParent == false.
+ * When the planner discovers that a relation is the root of an inheritance
+ * tree, it sets isParent true, and adds an additional PlanRowMark to the
+ * list for each child relation (including the target rel itself in its role
+ * as a child).  isParent is also set to true for the partitioned child
+ * relations, which are not scanned just like the root parent.  The child
+ * entries have rti == child rel's RT index and prti == parent's RT index,
+ * and can therefore be recognized as children by the fact that prti != rti.
+ * The parent's allMarkTypes field gets the OR of (1<<markType) across all
+ * its children (this definition allows children to use different markTypes).
+ *
+ * The planner also adds resjunk output columns to the plan that carry
+ * information sufficient to identify the locked or fetched rows.  When
+ * markType != ROW_MARK_COPY, these columns are named
+ *		tableoid%u			OID of table
+ *		ctid%u				TID of row
+ * The tableoid column is only present for an inheritance hierarchy.
+ * When markType == ROW_MARK_COPY, there is instead a single column named
+ *		wholerow%u			whole-row value of relation
+ * (An inheritance hierarchy could have all three resjunk output columns,
+ * if some children use a different markType than others.)
+ * In all three cases, %u represents the rowmark ID number (rowmarkId).
+ * This number is unique within a plan tree, except that child relation
+ * entries copy their parent's rowmarkId.  (Assigning unique numbers
+ * means we needn't renumber rowmarkIds when flattening subqueries, which
+ * would require finding and renaming the resjunk columns as well.)
+ * Note this means that all tables in an inheritance hierarchy share the
+ * same resjunk column names.  However, in an inherited UPDATE/DELETE the
+ * columns could have different physical column numbers in each subplan.
+ */
+typedef struct PlanRowMark
+{
+	NodeTag		type;
+	Index		rti;			/* range table index of markable relation */
+	Index		prti;			/* range table index of parent relation */
+	Index		rowmarkId;		/* unique identifier for resjunk columns */
+	RowMarkType markType;		/* see enum above */
+	int			allMarkTypes;	/* OR of (1<<markType) for all children */
+	LockClauseStrength strength;	/* LockingClause's strength, or LCS_NONE */
+	LockWaitPolicy waitPolicy;	/* NOWAIT and SKIP LOCKED options */
+	bool		isParent;		/* true if this is a "dummy" parent entry */
+} PlanRowMark;
+
+
+/*
+ * Node types to represent partition pruning information.
+ */
+
+/*
+ * PartitionPruneInfo - Details required to allow the executor to prune
+ * partitions.
+ *
+ * Here we store mapping details to allow translation of a partitioned table's
+ * index as returned by the partition pruning code into subplan indexes for
+ * plan types which support arbitrary numbers of subplans, such as Append.
+ * We also store various details to tell the executor when it should be
+ * performing partition pruning.
+ *
+ * Each PartitionedRelPruneInfo describes the partitioning rules for a single
+ * partitioned table (a/k/a level of partitioning).  Since a partitioning
+ * hierarchy could contain multiple levels, we represent it by a List of
+ * PartitionedRelPruneInfos, where the first entry represents the topmost
+ * partitioned table and additional entries represent non-leaf child
+ * partitions, ordered such that parents appear before their children.
+ * Then, since an Append-type node could have multiple partitioning
+ * hierarchies among its children, we have an unordered List of those Lists.
+ *
+ * prune_infos			List of Lists containing PartitionedRelPruneInfo nodes,
+ *						one sublist per run-time-prunable partition hierarchy
+ *						appearing in the parent plan node's subplans.
+ * other_subplans		Indexes of any subplans that are not accounted for
+ *						by any of the PartitionedRelPruneInfo nodes in
+ *						"prune_infos".  These subplans must not be pruned.
+ */
+typedef struct PartitionPruneInfo
+{
+	NodeTag		type;
+	List	   *prune_infos;
+	Bitmapset  *other_subplans;
+} PartitionPruneInfo;
+
+/*
+ * PartitionedRelPruneInfo - Details required to allow the executor to prune
+ * partitions for a single partitioned table.
+ *
+ * subplan_map[] and subpart_map[] are indexed by partition index of the
+ * partitioned table referenced by 'rtindex', the partition index being the
+ * order that the partitions are defined in the table's PartitionDesc.  For a
+ * leaf partition p, subplan_map[p] contains the zero-based index of the
+ * partition's subplan in the parent plan's subplan list; it is -1 if the
+ * partition is non-leaf or has been pruned.  For a non-leaf partition p,
+ * subpart_map[p] contains the zero-based index of that sub-partition's
+ * PartitionedRelPruneInfo in the hierarchy's PartitionedRelPruneInfo list;
+ * it is -1 if the partition is a leaf or has been pruned.  Note that subplan
+ * indexes, as stored in 'subplan_map', are global across the parent plan
+ * node, but partition indexes are valid only within a particular hierarchy.
+ * relid_map[p] contains the partition's OID, or 0 if the partition was pruned.
+ */
+typedef struct PartitionedRelPruneInfo
+{
+	NodeTag		type;
+	Index		rtindex;		/* RT index of partition rel for this level */
+	Bitmapset  *present_parts;	/* Indexes of all partitions which subplans or
+								 * subparts are present for */
+	int			nparts;			/* Length of the following arrays: */
+	int		   *subplan_map;	/* subplan index by partition index, or -1 */
+	int		   *subpart_map;	/* subpart index by partition index, or -1 */
+	Oid		   *relid_map;		/* relation OID by partition index, or 0 */
+
+	/*
+	 * initial_pruning_steps shows how to prune during executor startup (i.e.,
+	 * without use of any PARAM_EXEC Params); it is NIL if no startup pruning
+	 * is required.  exec_pruning_steps shows how to prune with PARAM_EXEC
+	 * Params; it is NIL if no per-scan pruning is required.
+	 */
+	List	   *initial_pruning_steps;	/* List of PartitionPruneStep */
+	List	   *exec_pruning_steps; /* List of PartitionPruneStep */
+	Bitmapset  *execparamids;	/* All PARAM_EXEC Param IDs in
+								 * exec_pruning_steps */
+} PartitionedRelPruneInfo;
+
+/*
+ * Abstract Node type for partition pruning steps (there are no concrete
+ * Nodes of this type).
+ *
+ * step_id is the global identifier of the step within its pruning context.
+ */
+typedef struct PartitionPruneStep
+{
+	NodeTag		type;
+	int			step_id;
+} PartitionPruneStep;
+
+/*
+ * PartitionPruneStepOp - Information to prune using a set of mutually AND'd
+ *							OpExpr clauses
+ *
+ * This contains information extracted from up to partnatts OpExpr clauses,
+ * where partnatts is the number of partition key columns.  'opstrategy' is the
+ * strategy of the operator in the clause matched to the last partition key.
+ * 'exprs' contains expressions which comprise the lookup key to be passed to
+ * the partition bound search function.  'cmpfns' contains the OIDs of
+ * comparison functions used to compare aforementioned expressions with
+ * partition bounds.  Both 'exprs' and 'cmpfns' contain the same number of
+ * items, up to partnatts items.
+ *
+ * Once we find the offset of a partition bound using the lookup key, we
+ * determine which partitions to include in the result based on the value of
+ * 'opstrategy'.  For example, if it were equality, we'd return just the
+ * partition that would contain that key or a set of partitions if the key
+ * didn't consist of all partitioning columns.  For non-equality strategies,
+ * we'd need to include other partitions as appropriate.
+ *
+ * 'nullkeys' is the set containing the offset of the partition keys (0 to
+ * partnatts - 1) that were matched to an IS NULL clause.  This is only
+ * considered for hash partitioning as we need to pass which keys are null
+ * to the hash partition bound search function.  It is never possible to
+ * have an expression be present in 'exprs' for a given partition key and
+ * the corresponding bit set in 'nullkeys'.
+ */
+typedef struct PartitionPruneStepOp
+{
+	PartitionPruneStep step;
+
+	StrategyNumber opstrategy;
+	List	   *exprs;
+	List	   *cmpfns;
+	Bitmapset  *nullkeys;
+} PartitionPruneStepOp;
+
+/*
+ * PartitionPruneStepCombine - Information to prune using a BoolExpr clause
+ *
+ * For BoolExpr clauses, we combine the set of partitions determined for each
+ * of the argument clauses.
+ */
+typedef enum PartitionPruneCombineOp
+{
+	PARTPRUNE_COMBINE_UNION,
+	PARTPRUNE_COMBINE_INTERSECT
+} PartitionPruneCombineOp;
+
+typedef struct PartitionPruneStepCombine
+{
+	PartitionPruneStep step;
+
+	PartitionPruneCombineOp combineOp;
+	List	   *source_stepids;
+} PartitionPruneStepCombine;
+
+
+/*
+ * Plan invalidation info
+ *
+ * We track the objects on which a PlannedStmt depends in two ways:
+ * relations are recorded as a simple list of OIDs, and everything else
+ * is represented as a list of PlanInvalItems.  A PlanInvalItem is designed
+ * to be used with the syscache invalidation mechanism, so it identifies a
+ * system catalog entry by cache ID and hash value.
+ */
+typedef struct PlanInvalItem
+{
+	NodeTag		type;
+	int			cacheId;		/* a syscache ID, see utils/syscache.h */
+	uint32		hashValue;		/* hash value of object's cache lookup key */
+} PlanInvalItem;
+
+#endif							/* PLANNODES_H */
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h
new file mode 100644
index 0000000..d73be2a
--- /dev/null
+++ b/src/include/nodes/primnodes.h
@@ -0,0 +1,1541 @@
+/*-------------------------------------------------------------------------
+ *
+ * primnodes.h
+ *	  Definitions for "primitive" node types, those that are used in more
+ *	  than one of the parse/plan/execute stages of the query pipeline.
+ *	  Currently, these are mostly nodes for executable expressions
+ *	  and join trees.
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/primnodes.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef PRIMNODES_H
+#define PRIMNODES_H
+
+#include "access/attnum.h"
+#include "nodes/bitmapset.h"
+#include "nodes/pg_list.h"
+
+
+/* ----------------------------------------------------------------
+ *						node definitions
+ * ----------------------------------------------------------------
+ */
+
+/*
+ * Alias -
+ *	  specifies an alias for a range variable; the alias might also
+ *	  specify renaming of columns within the table.
+ *
+ * Note: colnames is a list of Value nodes (always strings).  In Alias structs
+ * associated with RTEs, there may be entries corresponding to dropped
+ * columns; these are normally empty strings ("").  See parsenodes.h for info.
+ */
+typedef struct Alias
+{
+	NodeTag		type;
+	char	   *aliasname;		/* aliased rel name (never qualified) */
+	List	   *colnames;		/* optional list of column aliases */
+} Alias;
+
+/* What to do at commit time for temporary relations */
+typedef enum OnCommitAction
+{
+	ONCOMMIT_NOOP,				/* No ON COMMIT clause (do nothing) */
+	ONCOMMIT_PRESERVE_ROWS,		/* ON COMMIT PRESERVE ROWS (do nothing) */
+	ONCOMMIT_DELETE_ROWS,		/* ON COMMIT DELETE ROWS */
+	ONCOMMIT_DROP				/* ON COMMIT DROP */
+} OnCommitAction;
+
+/*
+ * RangeVar - range variable, used in FROM clauses
+ *
+ * Also used to represent table names in utility statements; there, the alias
+ * field is not used, and inh tells whether to apply the operation
+ * recursively to child tables.  In some contexts it is also useful to carry
+ * a TEMP table indication here.
+ */
+typedef struct RangeVar
+{
+	NodeTag		type;
+	char	   *catalogname;	/* the catalog (database) name, or NULL */
+	char	   *schemaname;		/* the schema name, or NULL */
+	char	   *relname;		/* the relation/sequence name */
+	bool		inh;			/* expand rel by inheritance? recursively act
+								 * on children? */
+	char		relpersistence; /* see RELPERSISTENCE_* in pg_class.h */
+	Alias	   *alias;			/* table alias & optional column aliases */
+	int			location;		/* token location, or -1 if unknown */
+} RangeVar;
+
+/*
+ * TableFunc - node for a table function, such as XMLTABLE.
+ *
+ * Entries in the ns_names list are either string Value nodes containing
+ * literal namespace names, or NULL pointers to represent DEFAULT.
+ */
+typedef struct TableFunc
+{
+	NodeTag		type;
+	List	   *ns_uris;		/* list of namespace URI expressions */
+	List	   *ns_names;		/* list of namespace names or NULL */
+	Node	   *docexpr;		/* input document expression */
+	Node	   *rowexpr;		/* row filter expression */
+	List	   *colnames;		/* column names (list of String) */
+	List	   *coltypes;		/* OID list of column type OIDs */
+	List	   *coltypmods;		/* integer list of column typmods */
+	List	   *colcollations;	/* OID list of column collation OIDs */
+	List	   *colexprs;		/* list of column filter expressions */
+	List	   *coldefexprs;	/* list of column default expressions */
+	Bitmapset  *notnulls;		/* nullability flag for each output column */
+	int			ordinalitycol;	/* counts from 0; -1 if none specified */
+	int			location;		/* token location, or -1 if unknown */
+} TableFunc;
+
+/*
+ * IntoClause - target information for SELECT INTO, CREATE TABLE AS, and
+ * CREATE MATERIALIZED VIEW
+ *
+ * For CREATE MATERIALIZED VIEW, viewQuery is the parsed-but-not-rewritten
+ * SELECT Query for the view; otherwise it's NULL.  (Although it's actually
+ * Query*, we declare it as Node* to avoid a forward reference.)
+ */
+typedef struct IntoClause
+{
+	NodeTag		type;
+
+	RangeVar   *rel;			/* target relation name */
+	List	   *colNames;		/* column names to assign, or NIL */
+	char	   *accessMethod;	/* table access method */
+	List	   *options;		/* options from WITH clause */
+	OnCommitAction onCommit;	/* what do we do at COMMIT? */
+	char	   *tableSpaceName; /* table space to use, or NULL */
+	Node	   *viewQuery;		/* materialized view's SELECT query */
+	bool		skipData;		/* true for WITH NO DATA */
+} IntoClause;
+
+
+/* ----------------------------------------------------------------
+ *					node types for executable expressions
+ * ----------------------------------------------------------------
+ */
+
+/*
+ * Expr - generic superclass for executable-expression nodes
+ *
+ * All node types that are used in executable expression trees should derive
+ * from Expr (that is, have Expr as their first field).  Since Expr only
+ * contains NodeTag, this is a formality, but it is an easy form of
+ * documentation.  See also the ExprState node types in execnodes.h.
+ */
+typedef struct Expr
+{
+	NodeTag		type;
+} Expr;
+
+/*
+ * Var - expression node representing a variable (ie, a table column)
+ *
+ * In the parser and planner, varno and varattno identify the semantic
+ * referent, which is a base-relation column unless the reference is to a join
+ * USING column that isn't semantically equivalent to either join input column
+ * (because it is a FULL join or the input column requires a type coercion).
+ * In those cases varno and varattno refer to the JOIN RTE.  (Early in the
+ * planner, we replace such join references by the implied expression; but up
+ * till then we want join reference Vars to keep their original identity for
+ * query-printing purposes.)
+ *
+ * At the end of planning, Var nodes appearing in upper-level plan nodes are
+ * reassigned to point to the outputs of their subplans; for example, in a
+ * join node varno becomes INNER_VAR or OUTER_VAR and varattno becomes the
+ * index of the proper element of that subplan's target list.  Similarly,
+ * INDEX_VAR is used to identify Vars that reference an index column rather
+ * than a heap column.  (In ForeignScan and CustomScan plan nodes, INDEX_VAR
+ * is abused to signify references to columns of a custom scan tuple type.)
+ *
+ * In the parser, varnosyn and varattnosyn are either identical to
+ * varno/varattno, or they specify the column's position in an aliased JOIN
+ * RTE that hides the semantic referent RTE's refname.  This is a syntactic
+ * identifier as opposed to the semantic identifier; it tells ruleutils.c
+ * how to print the Var properly.  varnosyn/varattnosyn retain their values
+ * throughout planning and execution, so they are particularly helpful to
+ * identify Vars when debugging.  Note, however, that a Var that is generated
+ * in the planner and doesn't correspond to any simple relation column may
+ * have varnosyn = varattnosyn = 0.
+ */
+#define    INNER_VAR		65000	/* reference to inner subplan */
+#define    OUTER_VAR		65001	/* reference to outer subplan */
+#define    INDEX_VAR		65002	/* reference to index column */
+
+#define IS_SPECIAL_VARNO(varno)		((varno) >= INNER_VAR)
+
+/* Symbols for the indexes of the special RTE entries in rules */
+#define    PRS2_OLD_VARNO			1
+#define    PRS2_NEW_VARNO			2
+
+typedef struct Var
+{
+	Expr		xpr;
+	Index		varno;			/* index of this var's relation in the range
+								 * table, or INNER_VAR/OUTER_VAR/INDEX_VAR */
+	AttrNumber	varattno;		/* attribute number of this var, or zero for
+								 * all attrs ("whole-row Var") */
+	Oid			vartype;		/* pg_type OID for the type of this var */
+	int32		vartypmod;		/* pg_attribute typmod value */
+	Oid			varcollid;		/* OID of collation, or InvalidOid if none */
+	Index		varlevelsup;	/* for subquery variables referencing outer
+								 * relations; 0 in a normal var, >0 means N
+								 * levels up */
+	Index		varnosyn;		/* syntactic relation index (0 if unknown) */
+	AttrNumber	varattnosyn;	/* syntactic attribute number */
+	int			location;		/* token location, or -1 if unknown */
+} Var;
+
+/*
+ * Const
+ *
+ * Note: for varlena data types, we make a rule that a Const node's value
+ * must be in non-extended form (4-byte header, no compression or external
+ * references).  This ensures that the Const node is self-contained and makes
+ * it more likely that equal() will see logically identical values as equal.
+ */
+typedef struct Const
+{
+	Expr		xpr;
+	Oid			consttype;		/* pg_type OID of the constant's datatype */
+	int32		consttypmod;	/* typmod value, if any */
+	Oid			constcollid;	/* OID of collation, or InvalidOid if none */
+	int			constlen;		/* typlen of the constant's datatype */
+	Datum		constvalue;		/* the constant's value */
+	bool		constisnull;	/* whether the constant is null (if true,
+								 * constvalue is undefined) */
+	bool		constbyval;		/* whether this datatype is passed by value.
+								 * If true, then all the information is stored
+								 * in the Datum. If false, then the Datum
+								 * contains a pointer to the information. */
+	int			location;		/* token location, or -1 if unknown */
+} Const;
+
+/*
+ * Param
+ *
+ *		paramkind specifies the kind of parameter. The possible values
+ *		for this field are:
+ *
+ *		PARAM_EXTERN:  The parameter value is supplied from outside the plan.
+ *				Such parameters are numbered from 1 to n.
+ *
+ *		PARAM_EXEC:  The parameter is an internal executor parameter, used
+ *				for passing values into and out of sub-queries or from
+ *				nestloop joins to their inner scans.
+ *				For historical reasons, such parameters are numbered from 0.
+ *				These numbers are independent of PARAM_EXTERN numbers.
+ *
+ *		PARAM_SUBLINK:	The parameter represents an output column of a SubLink
+ *				node's sub-select.  The column number is contained in the
+ *				`paramid' field.  (This type of Param is converted to
+ *				PARAM_EXEC during planning.)
+ *
+ *		PARAM_MULTIEXPR:  Like PARAM_SUBLINK, the parameter represents an
+ *				output column of a SubLink node's sub-select, but here, the
+ *				SubLink is always a MULTIEXPR SubLink.  The high-order 16 bits
+ *				of the `paramid' field contain the SubLink's subLinkId, and
+ *				the low-order 16 bits contain the column number.  (This type
+ *				of Param is also converted to PARAM_EXEC during planning.)
+ */
+typedef enum ParamKind
+{
+	PARAM_EXTERN,
+	PARAM_EXEC,
+	PARAM_SUBLINK,
+	PARAM_MULTIEXPR
+} ParamKind;
+
+typedef struct Param
+{
+	Expr		xpr;
+	ParamKind	paramkind;		/* kind of parameter. See above */
+	int			paramid;		/* numeric ID for parameter */
+	Oid			paramtype;		/* pg_type OID of parameter's datatype */
+	int32		paramtypmod;	/* typmod value, if known */
+	Oid			paramcollid;	/* OID of collation, or InvalidOid if none */
+	int			location;		/* token location, or -1 if unknown */
+} Param;
+
+/*
+ * Aggref
+ *
+ * The aggregate's args list is a targetlist, ie, a list of TargetEntry nodes.
+ *
+ * For a normal (non-ordered-set) aggregate, the non-resjunk TargetEntries
+ * represent the aggregate's regular arguments (if any) and resjunk TLEs can
+ * be added at the end to represent ORDER BY expressions that are not also
+ * arguments.  As in a top-level Query, the TLEs can be marked with
+ * ressortgroupref indexes to let them be referenced by SortGroupClause
+ * entries in the aggorder and/or aggdistinct lists.  This represents ORDER BY
+ * and DISTINCT operations to be applied to the aggregate input rows before
+ * they are passed to the transition function.  The grammar only allows a
+ * simple "DISTINCT" specifier for the arguments, but we use the full
+ * query-level representation to allow more code sharing.
+ *
+ * For an ordered-set aggregate, the args list represents the WITHIN GROUP
+ * (aggregated) arguments, all of which will be listed in the aggorder list.
+ * DISTINCT is not supported in this case, so aggdistinct will be NIL.
+ * The direct arguments appear in aggdirectargs (as a list of plain
+ * expressions, not TargetEntry nodes).
+ *
+ * aggtranstype is the data type of the state transition values for this
+ * aggregate (resolved to an actual type, if agg's transtype is polymorphic).
+ * This is determined during planning and is InvalidOid before that.
+ *
+ * aggargtypes is an OID list of the data types of the direct and regular
+ * arguments.  Normally it's redundant with the aggdirectargs and args lists,
+ * but in a combining aggregate, it's not because the args list has been
+ * replaced with a single argument representing the partial-aggregate
+ * transition values.
+ *
+ * aggsplit indicates the expected partial-aggregation mode for the Aggref's
+ * parent plan node.  It's always set to AGGSPLIT_SIMPLE in the parser, but
+ * the planner might change it to something else.  We use this mainly as
+ * a crosscheck that the Aggrefs match the plan; but note that when aggsplit
+ * indicates a non-final mode, aggtype reflects the transition data type
+ * not the SQL-level output type of the aggregate.
+ */
+typedef struct Aggref
+{
+	Expr		xpr;
+	Oid			aggfnoid;		/* pg_proc Oid of the aggregate */
+	Oid			aggtype;		/* type Oid of result of the aggregate */
+	Oid			aggcollid;		/* OID of collation of result */
+	Oid			inputcollid;	/* OID of collation that function should use */
+	Oid			aggtranstype;	/* type Oid of aggregate's transition value */
+	List	   *aggargtypes;	/* type Oids of direct and aggregated args */
+	List	   *aggdirectargs;	/* direct arguments, if an ordered-set agg */
+	List	   *args;			/* aggregated arguments and sort expressions */
+	List	   *aggorder;		/* ORDER BY (list of SortGroupClause) */
+	List	   *aggdistinct;	/* DISTINCT (list of SortGroupClause) */
+	Expr	   *aggfilter;		/* FILTER expression, if any */
+	bool		aggstar;		/* true if argument list was really '*' */
+	bool		aggvariadic;	/* true if variadic arguments have been
+								 * combined into an array last argument */
+	char		aggkind;		/* aggregate kind (see pg_aggregate.h) */
+	Index		agglevelsup;	/* > 0 if agg belongs to outer query */
+	AggSplit	aggsplit;		/* expected agg-splitting mode of parent Agg */
+	int			location;		/* token location, or -1 if unknown */
+} Aggref;
+
+/*
+ * GroupingFunc
+ *
+ * A GroupingFunc is a GROUPING(...) expression, which behaves in many ways
+ * like an aggregate function (e.g. it "belongs" to a specific query level,
+ * which might not be the one immediately containing it), but also differs in
+ * an important respect: it never evaluates its arguments, they merely
+ * designate expressions from the GROUP BY clause of the query level to which
+ * it belongs.
+ *
+ * The spec defines the evaluation of GROUPING() purely by syntactic
+ * replacement, but we make it a real expression for optimization purposes so
+ * that one Agg node can handle multiple grouping sets at once.  Evaluating the
+ * result only needs the column positions to check against the grouping set
+ * being projected.  However, for EXPLAIN to produce meaningful output, we have
+ * to keep the original expressions around, since expression deparse does not
+ * give us any feasible way to get at the GROUP BY clause.
+ *
+ * Also, we treat two GroupingFunc nodes as equal if they have equal arguments
+ * lists and agglevelsup, without comparing the refs and cols annotations.
+ *
+ * In raw parse output we have only the args list; parse analysis fills in the
+ * refs list, and the planner fills in the cols list.
+ */
+typedef struct GroupingFunc
+{
+	Expr		xpr;
+	List	   *args;			/* arguments, not evaluated but kept for
+								 * benefit of EXPLAIN etc. */
+	List	   *refs;			/* ressortgrouprefs of arguments */
+	List	   *cols;			/* actual column positions set by planner */
+	Index		agglevelsup;	/* same as Aggref.agglevelsup */
+	int			location;		/* token location */
+} GroupingFunc;
+
+/*
+ * WindowFunc
+ */
+typedef struct WindowFunc
+{
+	Expr		xpr;
+	Oid			winfnoid;		/* pg_proc Oid of the function */
+	Oid			wintype;		/* type Oid of result of the window function */
+	Oid			wincollid;		/* OID of collation of result */
+	Oid			inputcollid;	/* OID of collation that function should use */
+	List	   *args;			/* arguments to the window function */
+	Expr	   *aggfilter;		/* FILTER expression, if any */
+	Index		winref;			/* index of associated WindowClause */
+	bool		winstar;		/* true if argument list was really '*' */
+	bool		winagg;			/* is function a simple aggregate? */
+	int			location;		/* token location, or -1 if unknown */
+} WindowFunc;
+
+/* ----------------
+ *	SubscriptingRef: describes a subscripting operation over a container
+ *			(array, etc).
+ *
+ * A SubscriptingRef can describe fetching a single element from a container,
+ * fetching a part of container (e.g. array slice), storing a single element into
+ * a container, or storing a slice.  The "store" cases work with an
+ * initial container value and a source value that is inserted into the
+ * appropriate part of the container; the result of the operation is an
+ * entire new modified container value.
+ *
+ * If reflowerindexpr = NIL, then we are fetching or storing a single container
+ * element at the subscripts given by refupperindexpr. Otherwise we are
+ * fetching or storing a container slice, that is a rectangular subcontainer
+ * with lower and upper bounds given by the index expressions.
+ * reflowerindexpr must be the same length as refupperindexpr when it
+ * is not NIL.
+ *
+ * In the slice case, individual expressions in the subscript lists can be
+ * NULL, meaning "substitute the array's current lower or upper bound".
+ *
+ * Note: the result datatype is the element type when fetching a single
+ * element; but it is the array type when doing subarray fetch or either
+ * type of store.
+ *
+ * Note: for the cases where a container is returned, if refexpr yields a R/W
+ * expanded container, then the implementation is allowed to modify that object
+ * in-place and return the same object.)
+ * ----------------
+ */
+typedef struct SubscriptingRef
+{
+	Expr		xpr;
+	Oid			refcontainertype;	/* type of the container proper */
+	Oid			refelemtype;	/* type of the container elements */
+	int32		reftypmod;		/* typmod of the container (and elements too) */
+	Oid			refcollid;		/* OID of collation, or InvalidOid if none */
+	List	   *refupperindexpr;	/* expressions that evaluate to upper
+									 * container indexes */
+	List	   *reflowerindexpr;	/* expressions that evaluate to lower
+									 * container indexes, or NIL for single
+									 * container element */
+	Expr	   *refexpr;		/* the expression that evaluates to a
+								 * container value */
+
+	Expr	   *refassgnexpr;	/* expression for the source value, or NULL if
+								 * fetch */
+} SubscriptingRef;
+
+/*
+ * CoercionContext - distinguishes the allowed set of type casts
+ *
+ * NB: ordering of the alternatives is significant; later (larger) values
+ * allow more casts than earlier ones.
+ */
+typedef enum CoercionContext
+{
+	COERCION_IMPLICIT,			/* coercion in context of expression */
+	COERCION_ASSIGNMENT,		/* coercion in context of assignment */
+	COERCION_EXPLICIT			/* explicit cast operation */
+} CoercionContext;
+
+/*
+ * CoercionForm - how to display a node that could have come from a cast
+ *
+ * NB: equal() ignores CoercionForm fields, therefore this *must* not carry
+ * any semantically significant information.  We need that behavior so that
+ * the planner will consider equivalent implicit and explicit casts to be
+ * equivalent.  In cases where those actually behave differently, the coercion
+ * function's arguments will be different.
+ */
+typedef enum CoercionForm
+{
+	COERCE_EXPLICIT_CALL,		/* display as a function call */
+	COERCE_EXPLICIT_CAST,		/* display as an explicit cast */
+	COERCE_IMPLICIT_CAST		/* implicit cast, so hide it */
+} CoercionForm;
+
+/*
+ * FuncExpr - expression node for a function call
+ */
+typedef struct FuncExpr
+{
+	Expr		xpr;
+	Oid			funcid;			/* PG_PROC OID of the function */
+	Oid			funcresulttype; /* PG_TYPE OID of result value */
+	bool		funcretset;		/* true if function returns set */
+	bool		funcvariadic;	/* true if variadic arguments have been
+								 * combined into an array last argument */
+	CoercionForm funcformat;	/* how to display this function call */
+	Oid			funccollid;		/* OID of collation of result */
+	Oid			inputcollid;	/* OID of collation that function should use */
+	List	   *args;			/* arguments to the function */
+	int			location;		/* token location, or -1 if unknown */
+} FuncExpr;
+
+/*
+ * NamedArgExpr - a named argument of a function
+ *
+ * This node type can only appear in the args list of a FuncCall or FuncExpr
+ * node.  We support pure positional call notation (no named arguments),
+ * named notation (all arguments are named), and mixed notation (unnamed
+ * arguments followed by named ones).
+ *
+ * Parse analysis sets argnumber to the positional index of the argument,
+ * but doesn't rearrange the argument list.
+ *
+ * The planner will convert argument lists to pure positional notation
+ * during expression preprocessing, so execution never sees a NamedArgExpr.
+ */
+typedef struct NamedArgExpr
+{
+	Expr		xpr;
+	Expr	   *arg;			/* the argument expression */
+	char	   *name;			/* the name */
+	int			argnumber;		/* argument's number in positional notation */
+	int			location;		/* argument name location, or -1 if unknown */
+} NamedArgExpr;
+
+/*
+ * OpExpr - expression node for an operator invocation
+ *
+ * Semantically, this is essentially the same as a function call.
+ *
+ * Note that opfuncid is not necessarily filled in immediately on creation
+ * of the node.  The planner makes sure it is valid before passing the node
+ * tree to the executor, but during parsing/planning opfuncid can be 0.
+ */
+typedef struct OpExpr
+{
+	Expr		xpr;
+	Oid			opno;			/* PG_OPERATOR OID of the operator */
+	Oid			opfuncid;		/* PG_PROC OID of underlying function */
+	Oid			opresulttype;	/* PG_TYPE OID of result value */
+	bool		opretset;		/* true if operator returns set */
+	Oid			opcollid;		/* OID of collation of result */
+	Oid			inputcollid;	/* OID of collation that operator should use */
+	List	   *args;			/* arguments to the operator (1 or 2) */
+	int			location;		/* token location, or -1 if unknown */
+} OpExpr;
+
+/*
+ * DistinctExpr - expression node for "x IS DISTINCT FROM y"
+ *
+ * Except for the nodetag, this is represented identically to an OpExpr
+ * referencing the "=" operator for x and y.
+ * We use "=", not the more obvious "<>", because more datatypes have "="
+ * than "<>".  This means the executor must invert the operator result.
+ * Note that the operator function won't be called at all if either input
+ * is NULL, since then the result can be determined directly.
+ */
+typedef OpExpr DistinctExpr;
+
+/*
+ * NullIfExpr - a NULLIF expression
+ *
+ * Like DistinctExpr, this is represented the same as an OpExpr referencing
+ * the "=" operator for x and y.
+ */
+typedef OpExpr NullIfExpr;
+
+/*
+ * ScalarArrayOpExpr - expression node for "scalar op ANY/ALL (array)"
+ *
+ * The operator must yield boolean.  It is applied to the left operand
+ * and each element of the righthand array, and the results are combined
+ * with OR or AND (for ANY or ALL respectively).  The node representation
+ * is almost the same as for the underlying operator, but we need a useOr
+ * flag to remember whether it's ANY or ALL, and we don't have to store
+ * the result type (or the collation) because it must be boolean.
+ */
+typedef struct ScalarArrayOpExpr
+{
+	Expr		xpr;
+	Oid			opno;			/* PG_OPERATOR OID of the operator */
+	Oid			opfuncid;		/* PG_PROC OID of underlying function */
+	bool		useOr;			/* true for ANY, false for ALL */
+	Oid			inputcollid;	/* OID of collation that operator should use */
+	List	   *args;			/* the scalar and array operands */
+	int			location;		/* token location, or -1 if unknown */
+} ScalarArrayOpExpr;
+
+/*
+ * BoolExpr - expression node for the basic Boolean operators AND, OR, NOT
+ *
+ * Notice the arguments are given as a List.  For NOT, of course the list
+ * must always have exactly one element.  For AND and OR, there can be two
+ * or more arguments.
+ */
+typedef enum BoolExprType
+{
+	AND_EXPR, OR_EXPR, NOT_EXPR
+} BoolExprType;
+
+typedef struct BoolExpr
+{
+	Expr		xpr;
+	BoolExprType boolop;
+	List	   *args;			/* arguments to this expression */
+	int			location;		/* token location, or -1 if unknown */
+} BoolExpr;
+
+/*
+ * SubLink
+ *
+ * A SubLink represents a subselect appearing in an expression, and in some
+ * cases also the combining operator(s) just above it.  The subLinkType
+ * indicates the form of the expression represented:
+ *	EXISTS_SUBLINK		EXISTS(SELECT ...)
+ *	ALL_SUBLINK			(lefthand) op ALL (SELECT ...)
+ *	ANY_SUBLINK			(lefthand) op ANY (SELECT ...)
+ *	ROWCOMPARE_SUBLINK	(lefthand) op (SELECT ...)
+ *	EXPR_SUBLINK		(SELECT with single targetlist item ...)
+ *	MULTIEXPR_SUBLINK	(SELECT with multiple targetlist items ...)
+ *	ARRAY_SUBLINK		ARRAY(SELECT with single targetlist item ...)
+ *	CTE_SUBLINK			WITH query (never actually part of an expression)
+ * For ALL, ANY, and ROWCOMPARE, the lefthand is a list of expressions of the
+ * same length as the subselect's targetlist.  ROWCOMPARE will *always* have
+ * a list with more than one entry; if the subselect has just one target
+ * then the parser will create an EXPR_SUBLINK instead (and any operator
+ * above the subselect will be represented separately).
+ * ROWCOMPARE, EXPR, and MULTIEXPR require the subselect to deliver at most
+ * one row (if it returns no rows, the result is NULL).
+ * ALL, ANY, and ROWCOMPARE require the combining operators to deliver boolean
+ * results.  ALL and ANY combine the per-row results using AND and OR
+ * semantics respectively.
+ * ARRAY requires just one target column, and creates an array of the target
+ * column's type using any number of rows resulting from the subselect.
+ *
+ * SubLink is classed as an Expr node, but it is not actually executable;
+ * it must be replaced in the expression tree by a SubPlan node during
+ * planning.
+ *
+ * NOTE: in the raw output of gram.y, testexpr contains just the raw form
+ * of the lefthand expression (if any), and operName is the String name of
+ * the combining operator.  Also, subselect is a raw parsetree.  During parse
+ * analysis, the parser transforms testexpr into a complete boolean expression
+ * that compares the lefthand value(s) to PARAM_SUBLINK nodes representing the
+ * output columns of the subselect.  And subselect is transformed to a Query.
+ * This is the representation seen in saved rules and in the rewriter.
+ *
+ * In EXISTS, EXPR, MULTIEXPR, and ARRAY SubLinks, testexpr and operName
+ * are unused and are always null.
+ *
+ * subLinkId is currently used only for MULTIEXPR SubLinks, and is zero in
+ * other SubLinks.  This number identifies different multiple-assignment
+ * subqueries within an UPDATE statement's SET list.  It is unique only
+ * within a particular targetlist.  The output column(s) of the MULTIEXPR
+ * are referenced by PARAM_MULTIEXPR Params appearing elsewhere in the tlist.
+ *
+ * The CTE_SUBLINK case never occurs in actual SubLink nodes, but it is used
+ * in SubPlans generated for WITH subqueries.
+ */
+typedef enum SubLinkType
+{
+	EXISTS_SUBLINK,
+	ALL_SUBLINK,
+	ANY_SUBLINK,
+	ROWCOMPARE_SUBLINK,
+	EXPR_SUBLINK,
+	MULTIEXPR_SUBLINK,
+	ARRAY_SUBLINK,
+	CTE_SUBLINK					/* for SubPlans only */
+} SubLinkType;
+
+
+typedef struct SubLink
+{
+	Expr		xpr;
+	SubLinkType subLinkType;	/* see above */
+	int			subLinkId;		/* ID (1..n); 0 if not MULTIEXPR */
+	Node	   *testexpr;		/* outer-query test for ALL/ANY/ROWCOMPARE */
+	List	   *operName;		/* originally specified operator name */
+	Node	   *subselect;		/* subselect as Query* or raw parsetree */
+	int			location;		/* token location, or -1 if unknown */
+} SubLink;
+
+/*
+ * SubPlan - executable expression node for a subplan (sub-SELECT)
+ *
+ * The planner replaces SubLink nodes in expression trees with SubPlan
+ * nodes after it has finished planning the subquery.  SubPlan references
+ * a sub-plantree stored in the subplans list of the toplevel PlannedStmt.
+ * (We avoid a direct link to make it easier to copy expression trees
+ * without causing multiple processing of the subplan.)
+ *
+ * In an ordinary subplan, testexpr points to an executable expression
+ * (OpExpr, an AND/OR tree of OpExprs, or RowCompareExpr) for the combining
+ * operator(s); the left-hand arguments are the original lefthand expressions,
+ * and the right-hand arguments are PARAM_EXEC Param nodes representing the
+ * outputs of the sub-select.  (NOTE: runtime coercion functions may be
+ * inserted as well.)  This is just the same expression tree as testexpr in
+ * the original SubLink node, but the PARAM_SUBLINK nodes are replaced by
+ * suitably numbered PARAM_EXEC nodes.
+ *
+ * If the sub-select becomes an initplan rather than a subplan, the executable
+ * expression is part of the outer plan's expression tree (and the SubPlan
+ * node itself is not, but rather is found in the outer plan's initPlan
+ * list).  In this case testexpr is NULL to avoid duplication.
+ *
+ * The planner also derives lists of the values that need to be passed into
+ * and out of the subplan.  Input values are represented as a list "args" of
+ * expressions to be evaluated in the outer-query context (currently these
+ * args are always just Vars, but in principle they could be any expression).
+ * The values are assigned to the global PARAM_EXEC params indexed by parParam
+ * (the parParam and args lists must have the same ordering).  setParam is a
+ * list of the PARAM_EXEC params that are computed by the sub-select, if it
+ * is an initplan; they are listed in order by sub-select output column
+ * position.  (parParam and setParam are integer Lists, not Bitmapsets,
+ * because their ordering is significant.)
+ *
+ * Also, the planner computes startup and per-call costs for use of the
+ * SubPlan.  Note that these include the cost of the subquery proper,
+ * evaluation of the testexpr if any, and any hashtable management overhead.
+ */
+typedef struct SubPlan
+{
+	Expr		xpr;
+	/* Fields copied from original SubLink: */
+	SubLinkType subLinkType;	/* see above */
+	/* The combining operators, transformed to an executable expression: */
+	Node	   *testexpr;		/* OpExpr or RowCompareExpr expression tree */
+	List	   *paramIds;		/* IDs of Params embedded in the above */
+	/* Identification of the Plan tree to use: */
+	int			plan_id;		/* Index (from 1) in PlannedStmt.subplans */
+	/* Identification of the SubPlan for EXPLAIN and debugging purposes: */
+	char	   *plan_name;		/* A name assigned during planning */
+	/* Extra data useful for determining subplan's output type: */
+	Oid			firstColType;	/* Type of first column of subplan result */
+	int32		firstColTypmod; /* Typmod of first column of subplan result */
+	Oid			firstColCollation;	/* Collation of first column of subplan
+									 * result */
+	/* Information about execution strategy: */
+	bool		useHashTable;	/* true to store subselect output in a hash
+								 * table (implies we are doing "IN") */
+	bool		unknownEqFalse; /* true if it's okay to return FALSE when the
+								 * spec result is UNKNOWN; this allows much
+								 * simpler handling of null values */
+	bool		parallel_safe;	/* is the subplan parallel-safe? */
+	/* Note: parallel_safe does not consider contents of testexpr or args */
+	/* Information for passing params into and out of the subselect: */
+	/* setParam and parParam are lists of integers (param IDs) */
+	List	   *setParam;		/* initplan subqueries have to set these
+								 * Params for parent plan */
+	List	   *parParam;		/* indices of input Params from parent plan */
+	List	   *args;			/* exprs to pass as parParam values */
+	/* Estimated execution costs: */
+	Cost		startup_cost;	/* one-time setup cost */
+	Cost		per_call_cost;	/* cost for each subplan evaluation */
+} SubPlan;
+
+/*
+ * AlternativeSubPlan - expression node for a choice among SubPlans
+ *
+ * The subplans are given as a List so that the node definition need not
+ * change if there's ever more than two alternatives.  For the moment,
+ * though, there are always exactly two; and the first one is the fast-start
+ * plan.
+ */
+typedef struct AlternativeSubPlan
+{
+	Expr		xpr;
+	List	   *subplans;		/* SubPlan(s) with equivalent results */
+} AlternativeSubPlan;
+
+/* ----------------
+ * FieldSelect
+ *
+ * FieldSelect represents the operation of extracting one field from a tuple
+ * value.  At runtime, the input expression is expected to yield a rowtype
+ * Datum.  The specified field number is extracted and returned as a Datum.
+ * ----------------
+ */
+
+typedef struct FieldSelect
+{
+	Expr		xpr;
+	Expr	   *arg;			/* input expression */
+	AttrNumber	fieldnum;		/* attribute number of field to extract */
+	Oid			resulttype;		/* type of the field (result type of this
+								 * node) */
+	int32		resulttypmod;	/* output typmod (usually -1) */
+	Oid			resultcollid;	/* OID of collation of the field */
+} FieldSelect;
+
+/* ----------------
+ * FieldStore
+ *
+ * FieldStore represents the operation of modifying one field in a tuple
+ * value, yielding a new tuple value (the input is not touched!).  Like
+ * the assign case of SubscriptingRef, this is used to implement UPDATE of a
+ * portion of a column.
+ *
+ * resulttype is always a named composite type (not a domain).  To update
+ * a composite domain value, apply CoerceToDomain to the FieldStore.
+ *
+ * A single FieldStore can actually represent updates of several different
+ * fields.  The parser only generates FieldStores with single-element lists,
+ * but the planner will collapse multiple updates of the same base column
+ * into one FieldStore.
+ * ----------------
+ */
+
+typedef struct FieldStore
+{
+	Expr		xpr;
+	Expr	   *arg;			/* input tuple value */
+	List	   *newvals;		/* new value(s) for field(s) */
+	List	   *fieldnums;		/* integer list of field attnums */
+	Oid			resulttype;		/* type of result (same as type of arg) */
+	/* Like RowExpr, we deliberately omit a typmod and collation here */
+} FieldStore;
+
+/* ----------------
+ * RelabelType
+ *
+ * RelabelType represents a "dummy" type coercion between two binary-
+ * compatible datatypes, such as reinterpreting the result of an OID
+ * expression as an int4.  It is a no-op at runtime; we only need it
+ * to provide a place to store the correct type to be attributed to
+ * the expression result during type resolution.  (We can't get away
+ * with just overwriting the type field of the input expression node,
+ * so we need a separate node to show the coercion's result type.)
+ * ----------------
+ */
+
+typedef struct RelabelType
+{
+	Expr		xpr;
+	Expr	   *arg;			/* input expression */
+	Oid			resulttype;		/* output type of coercion expression */
+	int32		resulttypmod;	/* output typmod (usually -1) */
+	Oid			resultcollid;	/* OID of collation, or InvalidOid if none */
+	CoercionForm relabelformat; /* how to display this node */
+	int			location;		/* token location, or -1 if unknown */
+} RelabelType;
+
+/* ----------------
+ * CoerceViaIO
+ *
+ * CoerceViaIO represents a type coercion between two types whose textual
+ * representations are compatible, implemented by invoking the source type's
+ * typoutput function then the destination type's typinput function.
+ * ----------------
+ */
+
+typedef struct CoerceViaIO
+{
+	Expr		xpr;
+	Expr	   *arg;			/* input expression */
+	Oid			resulttype;		/* output type of coercion */
+	/* output typmod is not stored, but is presumed -1 */
+	Oid			resultcollid;	/* OID of collation, or InvalidOid if none */
+	CoercionForm coerceformat;	/* how to display this node */
+	int			location;		/* token location, or -1 if unknown */
+} CoerceViaIO;
+
+/* ----------------
+ * ArrayCoerceExpr
+ *
+ * ArrayCoerceExpr represents a type coercion from one array type to another,
+ * which is implemented by applying the per-element coercion expression
+ * "elemexpr" to each element of the source array.  Within elemexpr, the
+ * source element is represented by a CaseTestExpr node.  Note that even if
+ * elemexpr is a no-op (that is, just CaseTestExpr + RelabelType), the
+ * coercion still requires some effort: we have to fix the element type OID
+ * stored in the array header.
+ * ----------------
+ */
+
+typedef struct ArrayCoerceExpr
+{
+	Expr		xpr;
+	Expr	   *arg;			/* input expression (yields an array) */
+	Expr	   *elemexpr;		/* expression representing per-element work */
+	Oid			resulttype;		/* output type of coercion (an array type) */
+	int32		resulttypmod;	/* output typmod (also element typmod) */
+	Oid			resultcollid;	/* OID of collation, or InvalidOid if none */
+	CoercionForm coerceformat;	/* how to display this node */
+	int			location;		/* token location, or -1 if unknown */
+} ArrayCoerceExpr;
+
+/* ----------------
+ * ConvertRowtypeExpr
+ *
+ * ConvertRowtypeExpr represents a type coercion from one composite type
+ * to another, where the source type is guaranteed to contain all the columns
+ * needed for the destination type plus possibly others; the columns need not
+ * be in the same positions, but are matched up by name.  This is primarily
+ * used to convert a whole-row value of an inheritance child table into a
+ * valid whole-row value of its parent table's rowtype.  Both resulttype
+ * and the exposed type of "arg" must be named composite types (not domains).
+ * ----------------
+ */
+
+typedef struct ConvertRowtypeExpr
+{
+	Expr		xpr;
+	Expr	   *arg;			/* input expression */
+	Oid			resulttype;		/* output type (always a composite type) */
+	/* Like RowExpr, we deliberately omit a typmod and collation here */
+	CoercionForm convertformat; /* how to display this node */
+	int			location;		/* token location, or -1 if unknown */
+} ConvertRowtypeExpr;
+
+/*----------
+ * CollateExpr - COLLATE
+ *
+ * The planner replaces CollateExpr with RelabelType during expression
+ * preprocessing, so execution never sees a CollateExpr.
+ *----------
+ */
+typedef struct CollateExpr
+{
+	Expr		xpr;
+	Expr	   *arg;			/* input expression */
+	Oid			collOid;		/* collation's OID */
+	int			location;		/* token location, or -1 if unknown */
+} CollateExpr;
+
+/*----------
+ * CaseExpr - a CASE expression
+ *
+ * We support two distinct forms of CASE expression:
+ *		CASE WHEN boolexpr THEN expr [ WHEN boolexpr THEN expr ... ]
+ *		CASE testexpr WHEN compexpr THEN expr [ WHEN compexpr THEN expr ... ]
+ * These are distinguishable by the "arg" field being NULL in the first case
+ * and the testexpr in the second case.
+ *
+ * In the raw grammar output for the second form, the condition expressions
+ * of the WHEN clauses are just the comparison values.  Parse analysis
+ * converts these to valid boolean expressions of the form
+ *		CaseTestExpr '=' compexpr
+ * where the CaseTestExpr node is a placeholder that emits the correct
+ * value at runtime.  This structure is used so that the testexpr need be
+ * evaluated only once.  Note that after parse analysis, the condition
+ * expressions always yield boolean.
+ *
+ * Note: we can test whether a CaseExpr has been through parse analysis
+ * yet by checking whether casetype is InvalidOid or not.
+ *----------
+ */
+typedef struct CaseExpr
+{
+	Expr		xpr;
+	Oid			casetype;		/* type of expression result */
+	Oid			casecollid;		/* OID of collation, or InvalidOid if none */
+	Expr	   *arg;			/* implicit equality comparison argument */
+	List	   *args;			/* the arguments (list of WHEN clauses) */
+	Expr	   *defresult;		/* the default result (ELSE clause) */
+	int			location;		/* token location, or -1 if unknown */
+} CaseExpr;
+
+/*
+ * CaseWhen - one arm of a CASE expression
+ */
+typedef struct CaseWhen
+{
+	Expr		xpr;
+	Expr	   *expr;			/* condition expression */
+	Expr	   *result;			/* substitution result */
+	int			location;		/* token location, or -1 if unknown */
+} CaseWhen;
+
+/*
+ * Placeholder node for the test value to be processed by a CASE expression.
+ * This is effectively like a Param, but can be implemented more simply
+ * since we need only one replacement value at a time.
+ *
+ * We also abuse this node type for some other purposes, including:
+ *	* Placeholder for the current array element value in ArrayCoerceExpr;
+ *	  see build_coercion_expression().
+ *	* Nested FieldStore/SubscriptingRef assignment expressions in INSERT/UPDATE;
+ *	  see transformAssignmentIndirection().
+ *
+ * The uses in CaseExpr and ArrayCoerceExpr are safe only to the extent that
+ * there is not any other CaseExpr or ArrayCoerceExpr between the value source
+ * node and its child CaseTestExpr(s).  This is true in the parse analysis
+ * output, but the planner's function-inlining logic has to be careful not to
+ * break it.
+ *
+ * The nested-assignment-expression case is safe because the only node types
+ * that can be above such CaseTestExprs are FieldStore and SubscriptingRef.
+ */
+typedef struct CaseTestExpr
+{
+	Expr		xpr;
+	Oid			typeId;			/* type for substituted value */
+	int32		typeMod;		/* typemod for substituted value */
+	Oid			collation;		/* collation for the substituted value */
+} CaseTestExpr;
+
+/*
+ * ArrayExpr - an ARRAY[] expression
+ *
+ * Note: if multidims is false, the constituent expressions all yield the
+ * scalar type identified by element_typeid.  If multidims is true, the
+ * constituent expressions all yield arrays of element_typeid (ie, the same
+ * type as array_typeid); at runtime we must check for compatible subscripts.
+ */
+typedef struct ArrayExpr
+{
+	Expr		xpr;
+	Oid			array_typeid;	/* type of expression result */
+	Oid			array_collid;	/* OID of collation, or InvalidOid if none */
+	Oid			element_typeid; /* common type of array elements */
+	List	   *elements;		/* the array elements or sub-arrays */
+	bool		multidims;		/* true if elements are sub-arrays */
+	int			location;		/* token location, or -1 if unknown */
+} ArrayExpr;
+
+/*
+ * RowExpr - a ROW() expression
+ *
+ * Note: the list of fields must have a one-for-one correspondence with
+ * physical fields of the associated rowtype, although it is okay for it
+ * to be shorter than the rowtype.  That is, the N'th list element must
+ * match up with the N'th physical field.  When the N'th physical field
+ * is a dropped column (attisdropped) then the N'th list element can just
+ * be a NULL constant.  (This case can only occur for named composite types,
+ * not RECORD types, since those are built from the RowExpr itself rather
+ * than vice versa.)  It is important not to assume that length(args) is
+ * the same as the number of columns logically present in the rowtype.
+ *
+ * colnames provides field names in cases where the names can't easily be
+ * obtained otherwise.  Names *must* be provided if row_typeid is RECORDOID.
+ * If row_typeid identifies a known composite type, colnames can be NIL to
+ * indicate the type's cataloged field names apply.  Note that colnames can
+ * be non-NIL even for a composite type, and typically is when the RowExpr
+ * was created by expanding a whole-row Var.  This is so that we can retain
+ * the column alias names of the RTE that the Var referenced (which would
+ * otherwise be very difficult to extract from the parsetree).  Like the
+ * args list, colnames is one-for-one with physical fields of the rowtype.
+ */
+typedef struct RowExpr
+{
+	Expr		xpr;
+	List	   *args;			/* the fields */
+	Oid			row_typeid;		/* RECORDOID or a composite type's ID */
+
+	/*
+	 * row_typeid cannot be a domain over composite, only plain composite.  To
+	 * create a composite domain value, apply CoerceToDomain to the RowExpr.
+	 *
+	 * Note: we deliberately do NOT store a typmod.  Although a typmod will be
+	 * associated with specific RECORD types at runtime, it will differ for
+	 * different backends, and so cannot safely be stored in stored
+	 * parsetrees.  We must assume typmod -1 for a RowExpr node.
+	 *
+	 * We don't need to store a collation either.  The result type is
+	 * necessarily composite, and composite types never have a collation.
+	 */
+	CoercionForm row_format;	/* how to display this node */
+	List	   *colnames;		/* list of String, or NIL */
+	int			location;		/* token location, or -1 if unknown */
+} RowExpr;
+
+/*
+ * RowCompareExpr - row-wise comparison, such as (a, b) <= (1, 2)
+ *
+ * We support row comparison for any operator that can be determined to
+ * act like =, <>, <, <=, >, or >= (we determine this by looking for the
+ * operator in btree opfamilies).  Note that the same operator name might
+ * map to a different operator for each pair of row elements, since the
+ * element datatypes can vary.
+ *
+ * A RowCompareExpr node is only generated for the < <= > >= cases;
+ * the = and <> cases are translated to simple AND or OR combinations
+ * of the pairwise comparisons.  However, we include = and <> in the
+ * RowCompareType enum for the convenience of parser logic.
+ */
+typedef enum RowCompareType
+{
+	/* Values of this enum are chosen to match btree strategy numbers */
+	ROWCOMPARE_LT = 1,			/* BTLessStrategyNumber */
+	ROWCOMPARE_LE = 2,			/* BTLessEqualStrategyNumber */
+	ROWCOMPARE_EQ = 3,			/* BTEqualStrategyNumber */
+	ROWCOMPARE_GE = 4,			/* BTGreaterEqualStrategyNumber */
+	ROWCOMPARE_GT = 5,			/* BTGreaterStrategyNumber */
+	ROWCOMPARE_NE = 6			/* no such btree strategy */
+} RowCompareType;
+
+typedef struct RowCompareExpr
+{
+	Expr		xpr;
+	RowCompareType rctype;		/* LT LE GE or GT, never EQ or NE */
+	List	   *opnos;			/* OID list of pairwise comparison ops */
+	List	   *opfamilies;		/* OID list of containing operator families */
+	List	   *inputcollids;	/* OID list of collations for comparisons */
+	List	   *largs;			/* the left-hand input arguments */
+	List	   *rargs;			/* the right-hand input arguments */
+} RowCompareExpr;
+
+/*
+ * CoalesceExpr - a COALESCE expression
+ */
+typedef struct CoalesceExpr
+{
+	Expr		xpr;
+	Oid			coalescetype;	/* type of expression result */
+	Oid			coalescecollid; /* OID of collation, or InvalidOid if none */
+	List	   *args;			/* the arguments */
+	int			location;		/* token location, or -1 if unknown */
+} CoalesceExpr;
+
+/*
+ * MinMaxExpr - a GREATEST or LEAST function
+ */
+typedef enum MinMaxOp
+{
+	IS_GREATEST,
+	IS_LEAST
+} MinMaxOp;
+
+typedef struct MinMaxExpr
+{
+	Expr		xpr;
+	Oid			minmaxtype;		/* common type of arguments and result */
+	Oid			minmaxcollid;	/* OID of collation of result */
+	Oid			inputcollid;	/* OID of collation that function should use */
+	MinMaxOp	op;				/* function to execute */
+	List	   *args;			/* the arguments */
+	int			location;		/* token location, or -1 if unknown */
+} MinMaxExpr;
+
+/*
+ * SQLValueFunction - parameterless functions with special grammar productions
+ *
+ * The SQL standard categorizes some of these as <datetime value function>
+ * and others as <general value specification>.  We call 'em SQLValueFunctions
+ * for lack of a better term.  We store type and typmod of the result so that
+ * some code doesn't need to know each function individually, and because
+ * we would need to store typmod anyway for some of the datetime functions.
+ * Note that currently, all variants return non-collating datatypes, so we do
+ * not need a collation field; also, all these functions are stable.
+ */
+typedef enum SQLValueFunctionOp
+{
+	SVFOP_CURRENT_DATE,
+	SVFOP_CURRENT_TIME,
+	SVFOP_CURRENT_TIME_N,
+	SVFOP_CURRENT_TIMESTAMP,
+	SVFOP_CURRENT_TIMESTAMP_N,
+	SVFOP_LOCALTIME,
+	SVFOP_LOCALTIME_N,
+	SVFOP_LOCALTIMESTAMP,
+	SVFOP_LOCALTIMESTAMP_N,
+	SVFOP_CURRENT_ROLE,
+	SVFOP_CURRENT_USER,
+	SVFOP_USER,
+	SVFOP_SESSION_USER,
+	SVFOP_CURRENT_CATALOG,
+	SVFOP_CURRENT_SCHEMA
+} SQLValueFunctionOp;
+
+typedef struct SQLValueFunction
+{
+	Expr		xpr;
+	SQLValueFunctionOp op;		/* which function this is */
+	Oid			type;			/* result type/typmod */
+	int32		typmod;
+	int			location;		/* token location, or -1 if unknown */
+} SQLValueFunction;
+
+/*
+ * XmlExpr - various SQL/XML functions requiring special grammar productions
+ *
+ * 'name' carries the "NAME foo" argument (already XML-escaped).
+ * 'named_args' and 'arg_names' represent an xml_attribute list.
+ * 'args' carries all other arguments.
+ *
+ * Note: result type/typmod/collation are not stored, but can be deduced
+ * from the XmlExprOp.  The type/typmod fields are just used for display
+ * purposes, and are NOT necessarily the true result type of the node.
+ */
+typedef enum XmlExprOp
+{
+	IS_XMLCONCAT,				/* XMLCONCAT(args) */
+	IS_XMLELEMENT,				/* XMLELEMENT(name, xml_attributes, args) */
+	IS_XMLFOREST,				/* XMLFOREST(xml_attributes) */
+	IS_XMLPARSE,				/* XMLPARSE(text, is_doc, preserve_ws) */
+	IS_XMLPI,					/* XMLPI(name [, args]) */
+	IS_XMLROOT,					/* XMLROOT(xml, version, standalone) */
+	IS_XMLSERIALIZE,			/* XMLSERIALIZE(is_document, xmlval) */
+	IS_DOCUMENT					/* xmlval IS DOCUMENT */
+} XmlExprOp;
+
+typedef enum
+{
+	XMLOPTION_DOCUMENT,
+	XMLOPTION_CONTENT
+} XmlOptionType;
+
+typedef struct XmlExpr
+{
+	Expr		xpr;
+	XmlExprOp	op;				/* xml function ID */
+	char	   *name;			/* name in xml(NAME foo ...) syntaxes */
+	List	   *named_args;		/* non-XML expressions for xml_attributes */
+	List	   *arg_names;		/* parallel list of Value strings */
+	List	   *args;			/* list of expressions */
+	XmlOptionType xmloption;	/* DOCUMENT or CONTENT */
+	Oid			type;			/* target type/typmod for XMLSERIALIZE */
+	int32		typmod;
+	int			location;		/* token location, or -1 if unknown */
+} XmlExpr;
+
+/* ----------------
+ * NullTest
+ *
+ * NullTest represents the operation of testing a value for NULLness.
+ * The appropriate test is performed and returned as a boolean Datum.
+ *
+ * When argisrow is false, this simply represents a test for the null value.
+ *
+ * When argisrow is true, the input expression must yield a rowtype, and
+ * the node implements "row IS [NOT] NULL" per the SQL standard.  This
+ * includes checking individual fields for NULLness when the row datum
+ * itself isn't NULL.
+ *
+ * NOTE: the combination of a rowtype input and argisrow==false does NOT
+ * correspond to the SQL notation "row IS [NOT] NULL"; instead, this case
+ * represents the SQL notation "row IS [NOT] DISTINCT FROM NULL".
+ * ----------------
+ */
+
+typedef enum NullTestType
+{
+	IS_NULL, IS_NOT_NULL
+} NullTestType;
+
+typedef struct NullTest
+{
+	Expr		xpr;
+	Expr	   *arg;			/* input expression */
+	NullTestType nulltesttype;	/* IS NULL, IS NOT NULL */
+	bool		argisrow;		/* T to perform field-by-field null checks */
+	int			location;		/* token location, or -1 if unknown */
+} NullTest;
+
+/*
+ * BooleanTest
+ *
+ * BooleanTest represents the operation of determining whether a boolean
+ * is TRUE, FALSE, or UNKNOWN (ie, NULL).  All six meaningful combinations
+ * are supported.  Note that a NULL input does *not* cause a NULL result.
+ * The appropriate test is performed and returned as a boolean Datum.
+ */
+
+typedef enum BoolTestType
+{
+	IS_TRUE, IS_NOT_TRUE, IS_FALSE, IS_NOT_FALSE, IS_UNKNOWN, IS_NOT_UNKNOWN
+} BoolTestType;
+
+typedef struct BooleanTest
+{
+	Expr		xpr;
+	Expr	   *arg;			/* input expression */
+	BoolTestType booltesttype;	/* test type */
+	int			location;		/* token location, or -1 if unknown */
+} BooleanTest;
+
+/*
+ * CoerceToDomain
+ *
+ * CoerceToDomain represents the operation of coercing a value to a domain
+ * type.  At runtime (and not before) the precise set of constraints to be
+ * checked will be determined.  If the value passes, it is returned as the
+ * result; if not, an error is raised.  Note that this is equivalent to
+ * RelabelType in the scenario where no constraints are applied.
+ */
+typedef struct CoerceToDomain
+{
+	Expr		xpr;
+	Expr	   *arg;			/* input expression */
+	Oid			resulttype;		/* domain type ID (result type) */
+	int32		resulttypmod;	/* output typmod (currently always -1) */
+	Oid			resultcollid;	/* OID of collation, or InvalidOid if none */
+	CoercionForm coercionformat;	/* how to display this node */
+	int			location;		/* token location, or -1 if unknown */
+} CoerceToDomain;
+
+/*
+ * Placeholder node for the value to be processed by a domain's check
+ * constraint.  This is effectively like a Param, but can be implemented more
+ * simply since we need only one replacement value at a time.
+ *
+ * Note: the typeId/typeMod/collation will be set from the domain's base type,
+ * not the domain itself.  This is because we shouldn't consider the value
+ * to be a member of the domain if we haven't yet checked its constraints.
+ */
+typedef struct CoerceToDomainValue
+{
+	Expr		xpr;
+	Oid			typeId;			/* type for substituted value */
+	int32		typeMod;		/* typemod for substituted value */
+	Oid			collation;		/* collation for the substituted value */
+	int			location;		/* token location, or -1 if unknown */
+} CoerceToDomainValue;
+
+/*
+ * Placeholder node for a DEFAULT marker in an INSERT or UPDATE command.
+ *
+ * This is not an executable expression: it must be replaced by the actual
+ * column default expression during rewriting.  But it is convenient to
+ * treat it as an expression node during parsing and rewriting.
+ */
+typedef struct SetToDefault
+{
+	Expr		xpr;
+	Oid			typeId;			/* type for substituted value */
+	int32		typeMod;		/* typemod for substituted value */
+	Oid			collation;		/* collation for the substituted value */
+	int			location;		/* token location, or -1 if unknown */
+} SetToDefault;
+
+/*
+ * Node representing [WHERE] CURRENT OF cursor_name
+ *
+ * CURRENT OF is a bit like a Var, in that it carries the rangetable index
+ * of the target relation being constrained; this aids placing the expression
+ * correctly during planning.  We can assume however that its "levelsup" is
+ * always zero, due to the syntactic constraints on where it can appear.
+ *
+ * The referenced cursor can be represented either as a hardwired string
+ * or as a reference to a run-time parameter of type REFCURSOR.  The latter
+ * case is for the convenience of plpgsql.
+ */
+typedef struct CurrentOfExpr
+{
+	Expr		xpr;
+	Index		cvarno;			/* RT index of target relation */
+	char	   *cursor_name;	/* name of referenced cursor, or NULL */
+	int			cursor_param;	/* refcursor parameter number, or 0 */
+} CurrentOfExpr;
+
+/*
+ * NextValueExpr - get next value from sequence
+ *
+ * This has the same effect as calling the nextval() function, but it does not
+ * check permissions on the sequence.  This is used for identity columns,
+ * where the sequence is an implicit dependency without its own permissions.
+ */
+typedef struct NextValueExpr
+{
+	Expr		xpr;
+	Oid			seqid;
+	Oid			typeId;
+} NextValueExpr;
+
+/*
+ * InferenceElem - an element of a unique index inference specification
+ *
+ * This mostly matches the structure of IndexElems, but having a dedicated
+ * primnode allows for a clean separation between the use of index parameters
+ * by utility commands, and this node.
+ */
+typedef struct InferenceElem
+{
+	Expr		xpr;
+	Node	   *expr;			/* expression to infer from, or NULL */
+	Oid			infercollid;	/* OID of collation, or InvalidOid */
+	Oid			inferopclass;	/* OID of att opclass, or InvalidOid */
+} InferenceElem;
+
+/*--------------------
+ * TargetEntry -
+ *	   a target entry (used in query target lists)
+ *
+ * Strictly speaking, a TargetEntry isn't an expression node (since it can't
+ * be evaluated by ExecEvalExpr).  But we treat it as one anyway, since in
+ * very many places it's convenient to process a whole query targetlist as a
+ * single expression tree.
+ *
+ * In a SELECT's targetlist, resno should always be equal to the item's
+ * ordinal position (counting from 1).  However, in an INSERT or UPDATE
+ * targetlist, resno represents the attribute number of the destination
+ * column for the item; so there may be missing or out-of-order resnos.
+ * It is even legal to have duplicated resnos; consider
+ *		UPDATE table SET arraycol[1] = ..., arraycol[2] = ..., ...
+ * The two meanings come together in the executor, because the planner
+ * transforms INSERT/UPDATE tlists into a normalized form with exactly
+ * one entry for each column of the destination table.  Before that's
+ * happened, however, it is risky to assume that resno == position.
+ * Generally get_tle_by_resno() should be used rather than list_nth()
+ * to fetch tlist entries by resno, and only in SELECT should you assume
+ * that resno is a unique identifier.
+ *
+ * resname is required to represent the correct column name in non-resjunk
+ * entries of top-level SELECT targetlists, since it will be used as the
+ * column title sent to the frontend.  In most other contexts it is only
+ * a debugging aid, and may be wrong or even NULL.  (In particular, it may
+ * be wrong in a tlist from a stored rule, if the referenced column has been
+ * renamed by ALTER TABLE since the rule was made.  Also, the planner tends
+ * to store NULL rather than look up a valid name for tlist entries in
+ * non-toplevel plan nodes.)  In resjunk entries, resname should be either
+ * a specific system-generated name (such as "ctid") or NULL; anything else
+ * risks confusing ExecGetJunkAttribute!
+ *
+ * ressortgroupref is used in the representation of ORDER BY, GROUP BY, and
+ * DISTINCT items.  Targetlist entries with ressortgroupref=0 are not
+ * sort/group items.  If ressortgroupref>0, then this item is an ORDER BY,
+ * GROUP BY, and/or DISTINCT target value.  No two entries in a targetlist
+ * may have the same nonzero ressortgroupref --- but there is no particular
+ * meaning to the nonzero values, except as tags.  (For example, one must
+ * not assume that lower ressortgroupref means a more significant sort key.)
+ * The order of the associated SortGroupClause lists determine the semantics.
+ *
+ * resorigtbl/resorigcol identify the source of the column, if it is a
+ * simple reference to a column of a base table (or view).  If it is not
+ * a simple reference, these fields are zeroes.
+ *
+ * If resjunk is true then the column is a working column (such as a sort key)
+ * that should be removed from the final output of the query.  Resjunk columns
+ * must have resnos that cannot duplicate any regular column's resno.  Also
+ * note that there are places that assume resjunk columns come after non-junk
+ * columns.
+ *--------------------
+ */
+typedef struct TargetEntry
+{
+	Expr		xpr;
+	Expr	   *expr;			/* expression to evaluate */
+	AttrNumber	resno;			/* attribute number (see notes above) */
+	char	   *resname;		/* name of the column (could be NULL) */
+	Index		ressortgroupref;	/* nonzero if referenced by a sort/group
+									 * clause */
+	Oid			resorigtbl;		/* OID of column's source table */
+	AttrNumber	resorigcol;		/* column's number in source table */
+	bool		resjunk;		/* set to true to eliminate the attribute from
+								 * final target list */
+} TargetEntry;
+
+
+/* ----------------------------------------------------------------
+ *					node types for join trees
+ *
+ * The leaves of a join tree structure are RangeTblRef nodes.  Above
+ * these, JoinExpr nodes can appear to denote a specific kind of join
+ * or qualified join.  Also, FromExpr nodes can appear to denote an
+ * ordinary cross-product join ("FROM foo, bar, baz WHERE ...").
+ * FromExpr is like a JoinExpr of jointype JOIN_INNER, except that it
+ * may have any number of child nodes, not just two.
+ *
+ * NOTE: the top level of a Query's jointree is always a FromExpr.
+ * Even if the jointree contains no rels, there will be a FromExpr.
+ *
+ * NOTE: the qualification expressions present in JoinExpr nodes are
+ * *in addition to* the query's main WHERE clause, which appears as the
+ * qual of the top-level FromExpr.  The reason for associating quals with
+ * specific nodes in the jointree is that the position of a qual is critical
+ * when outer joins are present.  (If we enforce a qual too soon or too late,
+ * that may cause the outer join to produce the wrong set of NULL-extended
+ * rows.)  If all joins are inner joins then all the qual positions are
+ * semantically interchangeable.
+ *
+ * NOTE: in the raw output of gram.y, a join tree contains RangeVar,
+ * RangeSubselect, and RangeFunction nodes, which are all replaced by
+ * RangeTblRef nodes during the parse analysis phase.  Also, the top-level
+ * FromExpr is added during parse analysis; the grammar regards FROM and
+ * WHERE as separate.
+ * ----------------------------------------------------------------
+ */
+
+/*
+ * RangeTblRef - reference to an entry in the query's rangetable
+ *
+ * We could use direct pointers to the RT entries and skip having these
+ * nodes, but multiple pointers to the same node in a querytree cause
+ * lots of headaches, so it seems better to store an index into the RT.
+ */
+typedef struct RangeTblRef
+{
+	NodeTag		type;
+	int			rtindex;
+} RangeTblRef;
+
+/*----------
+ * JoinExpr - for SQL JOIN expressions
+ *
+ * isNatural, usingClause, and quals are interdependent.  The user can write
+ * only one of NATURAL, USING(), or ON() (this is enforced by the grammar).
+ * If he writes NATURAL then parse analysis generates the equivalent USING()
+ * list, and from that fills in "quals" with the right equality comparisons.
+ * If he writes USING() then "quals" is filled with equality comparisons.
+ * If he writes ON() then only "quals" is set.  Note that NATURAL/USING
+ * are not equivalent to ON() since they also affect the output column list.
+ *
+ * alias is an Alias node representing the AS alias-clause attached to the
+ * join expression, or NULL if no clause.  NB: presence or absence of the
+ * alias has a critical impact on semantics, because a join with an alias
+ * restricts visibility of the tables/columns inside it.
+ *
+ * During parse analysis, an RTE is created for the Join, and its index
+ * is filled into rtindex.  This RTE is present mainly so that Vars can
+ * be created that refer to the outputs of the join.  The planner sometimes
+ * generates JoinExprs internally; these can have rtindex = 0 if there are
+ * no join alias variables referencing such joins.
+ *----------
+ */
+typedef struct JoinExpr
+{
+	NodeTag		type;
+	JoinType	jointype;		/* type of join */
+	bool		isNatural;		/* Natural join? Will need to shape table */
+	Node	   *larg;			/* left subtree */
+	Node	   *rarg;			/* right subtree */
+	List	   *usingClause;	/* USING clause, if any (list of String) */
+	Node	   *quals;			/* qualifiers on join, if any */
+	Alias	   *alias;			/* user-written alias clause, if any */
+	int			rtindex;		/* RT index assigned for join, or 0 */
+} JoinExpr;
+
+/*----------
+ * FromExpr - represents a FROM ... WHERE ... construct
+ *
+ * This is both more flexible than a JoinExpr (it can have any number of
+ * children, including zero) and less so --- we don't need to deal with
+ * aliases and so on.  The output column set is implicitly just the union
+ * of the outputs of the children.
+ *----------
+ */
+typedef struct FromExpr
+{
+	NodeTag		type;
+	List	   *fromlist;		/* List of join subtrees */
+	Node	   *quals;			/* qualifiers on join, if any */
+} FromExpr;
+
+/*----------
+ * OnConflictExpr - represents an ON CONFLICT DO ... expression
+ *
+ * The optimizer requires a list of inference elements, and optionally a WHERE
+ * clause to infer a unique index.  The unique index (or, occasionally,
+ * indexes) inferred are used to arbitrate whether or not the alternative ON
+ * CONFLICT path is taken.
+ *----------
+ */
+typedef struct OnConflictExpr
+{
+	NodeTag		type;
+	OnConflictAction action;	/* DO NOTHING or UPDATE? */
+
+	/* Arbiter */
+	List	   *arbiterElems;	/* unique index arbiter list (of
+								 * InferenceElem's) */
+	Node	   *arbiterWhere;	/* unique index arbiter WHERE clause */
+	Oid			constraint;		/* pg_constraint OID for arbiter */
+
+	/* ON CONFLICT UPDATE */
+	List	   *onConflictSet;	/* List of ON CONFLICT SET TargetEntrys */
+	Node	   *onConflictWhere;	/* qualifiers to restrict UPDATE to */
+	int			exclRelIndex;	/* RT index of 'excluded' relation */
+	List	   *exclRelTlist;	/* tlist of the EXCLUDED pseudo relation */
+} OnConflictExpr;
+
+#endif							/* PRIMNODES_H */
diff --git a/src/include/nodes/print.h b/src/include/nodes/print.h
new file mode 100644
index 0000000..6126b49
--- /dev/null
+++ b/src/include/nodes/print.h
@@ -0,0 +1,34 @@
+/*-------------------------------------------------------------------------
+ *
+ * print.h
+ *	  definitions for nodes/print.c
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/print.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef PRINT_H
+#define PRINT_H
+
+#include "executor/tuptable.h"
+
+
+#define nodeDisplay(x)		pprint(x)
+
+extern void print(const void *obj);
+extern void pprint(const void *obj);
+extern void elog_node_display(int lev, const char *title,
+							  const void *obj, bool pretty);
+extern char *format_node_dump(const char *dump);
+extern char *pretty_format_node_dump(const char *dump);
+extern void print_rt(const List *rtable);
+extern void print_expr(const Node *expr, const List *rtable);
+extern void print_pathkeys(const List *pathkeys, const List *rtable);
+extern void print_tl(const List *tlist, const List *rtable);
+extern void print_slot(TupleTableSlot *slot);
+
+#endif							/* PRINT_H */
diff --git a/src/include/nodes/readfuncs.h b/src/include/nodes/readfuncs.h
new file mode 100644
index 0000000..4eb04ca
--- /dev/null
+++ b/src/include/nodes/readfuncs.h
@@ -0,0 +1,38 @@
+/*-------------------------------------------------------------------------
+ *
+ * readfuncs.h
+ *	  header file for read.c and readfuncs.c. These functions are internal
+ *	  to the stringToNode interface and should not be used by anyone else.
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/readfuncs.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef READFUNCS_H
+#define READFUNCS_H
+
+#include "nodes/nodes.h"
+
+/*
+ * variable in read.c that needs to be accessible to readfuncs.c
+ */
+#ifdef WRITE_READ_PARSE_PLAN_TREES
+extern bool restore_location_fields;
+#endif
+
+/*
+ * prototypes for functions in read.c (the lisp token parser)
+ */
+extern const char *pg_strtok(int *length);
+extern char *debackslash(const char *token, int length);
+extern void *nodeRead(const char *token, int tok_len);
+
+/*
+ * prototypes for functions in readfuncs.c
+ */
+extern Node *parseNodeString(void);
+
+#endif							/* READFUNCS_H */
diff --git a/src/include/nodes/replnodes.h b/src/include/nodes/replnodes.h
new file mode 100644
index 0000000..5456141
--- /dev/null
+++ b/src/include/nodes/replnodes.h
@@ -0,0 +1,109 @@
+/*-------------------------------------------------------------------------
+ *
+ * replnodes.h
+ *	  definitions for replication grammar parse nodes
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/replnodes.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef REPLNODES_H
+#define REPLNODES_H
+
+#include "access/xlogdefs.h"
+#include "nodes/pg_list.h"
+
+typedef enum ReplicationKind
+{
+	REPLICATION_KIND_PHYSICAL,
+	REPLICATION_KIND_LOGICAL
+} ReplicationKind;
+
+
+/* ----------------------
+ *		IDENTIFY_SYSTEM command
+ * ----------------------
+ */
+typedef struct IdentifySystemCmd
+{
+	NodeTag		type;
+} IdentifySystemCmd;
+
+
+/* ----------------------
+ *		BASE_BACKUP command
+ * ----------------------
+ */
+typedef struct BaseBackupCmd
+{
+	NodeTag		type;
+	List	   *options;
+} BaseBackupCmd;
+
+
+/* ----------------------
+ *		CREATE_REPLICATION_SLOT command
+ * ----------------------
+ */
+typedef struct CreateReplicationSlotCmd
+{
+	NodeTag		type;
+	char	   *slotname;
+	ReplicationKind kind;
+	char	   *plugin;
+	bool		temporary;
+	List	   *options;
+} CreateReplicationSlotCmd;
+
+
+/* ----------------------
+ *		DROP_REPLICATION_SLOT command
+ * ----------------------
+ */
+typedef struct DropReplicationSlotCmd
+{
+	NodeTag		type;
+	char	   *slotname;
+	bool		wait;
+} DropReplicationSlotCmd;
+
+
+/* ----------------------
+ *		START_REPLICATION command
+ * ----------------------
+ */
+typedef struct StartReplicationCmd
+{
+	NodeTag		type;
+	ReplicationKind kind;
+	char	   *slotname;
+	TimeLineID	timeline;
+	XLogRecPtr	startpoint;
+	List	   *options;
+} StartReplicationCmd;
+
+
+/* ----------------------
+ *		TIMELINE_HISTORY command
+ * ----------------------
+ */
+typedef struct TimeLineHistoryCmd
+{
+	NodeTag		type;
+	TimeLineID	timeline;
+} TimeLineHistoryCmd;
+
+/* ----------------------
+ *		SQL commands
+ * ----------------------
+ */
+typedef struct SQLCmd
+{
+	NodeTag		type;
+} SQLCmd;
+
+#endif							/* REPLNODES_H */
diff --git a/src/include/nodes/supportnodes.h b/src/include/nodes/supportnodes.h
new file mode 100644
index 0000000..9a33c4c
--- /dev/null
+++ b/src/include/nodes/supportnodes.h
@@ -0,0 +1,242 @@
+/*-------------------------------------------------------------------------
+ *
+ * supportnodes.h
+ *	  Definitions for planner support functions.
+ *
+ * This file defines the API for "planner support functions", which
+ * are SQL functions (normally written in C) that can be attached to
+ * another "target" function to give the system additional knowledge
+ * about the target function.  All the current capabilities have to do
+ * with planning queries that use the target function, though it is
+ * possible that future extensions will add functionality to be invoked
+ * by the parser or executor.
+ *
+ * A support function must have the SQL signature
+ *		supportfn(internal) returns internal
+ * The argument is a pointer to one of the Node types defined in this file.
+ * The result is usually also a Node pointer, though its type depends on
+ * which capability is being invoked.  In all cases, a NULL pointer result
+ * (that's PG_RETURN_POINTER(NULL), not PG_RETURN_NULL()) indicates that
+ * the support function cannot do anything useful for the given request.
+ * Support functions must return a NULL pointer, not fail, if they do not
+ * recognize the request node type or cannot handle the given case; this
+ * allows for future extensions of the set of request cases.
+ *
+ *
+ * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/nodes/supportnodes.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef SUPPORTNODES_H
+#define SUPPORTNODES_H
+
+#include "nodes/primnodes.h"
+
+struct PlannerInfo;				/* avoid including pathnodes.h here */
+struct IndexOptInfo;
+struct SpecialJoinInfo;
+
+
+/*
+ * The Simplify request allows the support function to perform plan-time
+ * simplification of a call to its target function.  For example, a varchar
+ * length coercion that does not decrease the allowed length of its argument
+ * could be replaced by a RelabelType node, or "x + 0" could be replaced by
+ * "x".  This is invoked during the planner's constant-folding pass, so the
+ * function's arguments can be presumed already simplified.
+ *
+ * The planner's PlannerInfo "root" is typically not needed, but can be
+ * consulted if it's necessary to obtain info about Vars present in
+ * the given node tree.  Beware that root could be NULL in some usages.
+ *
+ * "fcall" will be a FuncExpr invoking the support function's target
+ * function.  (This is true even if the original parsetree node was an
+ * operator call; a FuncExpr is synthesized for this purpose.)
+ *
+ * The result should be a semantically-equivalent transformed node tree,
+ * or NULL if no simplification could be performed.  Do *not* return or
+ * modify *fcall, as it isn't really a separately allocated Node.  But
+ * it's okay to use fcall->args, or parts of it, in the result tree.
+ */
+typedef struct SupportRequestSimplify
+{
+	NodeTag		type;
+
+	struct PlannerInfo *root;	/* Planner's infrastructure */
+	FuncExpr   *fcall;			/* Function call to be simplified */
+} SupportRequestSimplify;
+
+/*
+ * The Selectivity request allows the support function to provide a
+ * selectivity estimate for a function appearing at top level of a WHERE
+ * clause (so it applies only to functions returning boolean).
+ *
+ * The input arguments are the same as are supplied to operator restriction
+ * and join estimators, except that we unify those two APIs into just one
+ * request type.  See clause_selectivity() for the details.
+ *
+ * If an estimate can be made, store it into the "selectivity" field and
+ * return the address of the SupportRequestSelectivity node; the estimate
+ * must be between 0 and 1 inclusive.  Return NULL if no estimate can be
+ * made (in which case the planner will fall back to a default estimate,
+ * traditionally 1/3).
+ *
+ * If the target function is being used as the implementation of an operator,
+ * the support function will not be used for this purpose; the operator's
+ * restriction or join estimator is consulted instead.
+ */
+typedef struct SupportRequestSelectivity
+{
+	NodeTag		type;
+
+	/* Input fields: */
+	struct PlannerInfo *root;	/* Planner's infrastructure */
+	Oid			funcid;			/* function we are inquiring about */
+	List	   *args;			/* pre-simplified arguments to function */
+	Oid			inputcollid;	/* function's input collation */
+	bool		is_join;		/* is this a join or restriction case? */
+	int			varRelid;		/* if restriction, RTI of target relation */
+	JoinType	jointype;		/* if join, outer join type */
+	struct SpecialJoinInfo *sjinfo; /* if outer join, info about join */
+
+	/* Output fields: */
+	Selectivity selectivity;	/* returned selectivity estimate */
+} SupportRequestSelectivity;
+
+/*
+ * The Cost request allows the support function to provide an execution
+ * cost estimate for its target function.  The cost estimate can include
+ * both a one-time (query startup) component and a per-execution component.
+ * The estimate should *not* include the costs of evaluating the target
+ * function's arguments, only the target function itself.
+ *
+ * The "node" argument is normally the parse node that is invoking the
+ * target function.  This is a FuncExpr in the simplest case, but it could
+ * also be an OpExpr, DistinctExpr, NullIfExpr, or WindowFunc, or possibly
+ * other cases in future.  NULL is passed if the function cannot presume
+ * its arguments to be equivalent to what the calling node presents as
+ * arguments; that happens for, e.g., aggregate support functions and
+ * per-column comparison operators used by RowExprs.
+ *
+ * If an estimate can be made, store it into the cost fields and return the
+ * address of the SupportRequestCost node.  Return NULL if no estimate can be
+ * made, in which case the planner will rely on the target function's procost
+ * field.  (Note: while procost is automatically scaled by cpu_operator_cost,
+ * this is not the case for the outputs of the Cost request; the support
+ * function must scale its results appropriately on its own.)
+ */
+typedef struct SupportRequestCost
+{
+	NodeTag		type;
+
+	/* Input fields: */
+	struct PlannerInfo *root;	/* Planner's infrastructure (could be NULL) */
+	Oid			funcid;			/* function we are inquiring about */
+	Node	   *node;			/* parse node invoking function, or NULL */
+
+	/* Output fields: */
+	Cost		startup;		/* one-time cost */
+	Cost		per_tuple;		/* per-evaluation cost */
+} SupportRequestCost;
+
+/*
+ * The Rows request allows the support function to provide an output rowcount
+ * estimate for its target function (so it applies only to set-returning
+ * functions).
+ *
+ * The "node" argument is the parse node that is invoking the target function;
+ * currently this will always be a FuncExpr or OpExpr.
+ *
+ * If an estimate can be made, store it into the rows field and return the
+ * address of the SupportRequestRows node.  Return NULL if no estimate can be
+ * made, in which case the planner will rely on the target function's prorows
+ * field.
+ */
+typedef struct SupportRequestRows
+{
+	NodeTag		type;
+
+	/* Input fields: */
+	struct PlannerInfo *root;	/* Planner's infrastructure (could be NULL) */
+	Oid			funcid;			/* function we are inquiring about */
+	Node	   *node;			/* parse node invoking function */
+
+	/* Output fields: */
+	double		rows;			/* number of rows expected to be returned */
+} SupportRequestRows;
+
+/*
+ * The IndexCondition request allows the support function to generate
+ * a directly-indexable condition based on a target function call that is
+ * not itself indexable.  The target function call must appear at the top
+ * level of WHERE or JOIN/ON, so this applies only to functions returning
+ * boolean.
+ *
+ * The "node" argument is the parse node that is invoking the target function;
+ * currently this will always be a FuncExpr or OpExpr.  The call is made
+ * only if at least one function argument matches an index column's variable
+ * or expression.  "indexarg" identifies the matching argument (it's the
+ * argument's zero-based index in the node's args list).
+ *
+ * If the transformation is possible, return a List of directly-indexable
+ * condition expressions, else return NULL.  (A List is used because it's
+ * sometimes useful to generate more than one indexable condition, such as
+ * when a LIKE with constant prefix gives rise to both >= and < conditions.)
+ *
+ * "Directly indexable" means that the condition must be directly executable
+ * by the index machinery.  Typically this means that it is a binary OpExpr
+ * with the index column value on the left, a pseudo-constant on the right,
+ * and an operator that is in the index column's operator family.  Other
+ * possibilities include RowCompareExpr, ScalarArrayOpExpr, and NullTest,
+ * depending on the index type; but those seem less likely to be useful for
+ * derived index conditions.  "Pseudo-constant" means that the right-hand
+ * expression must not contain any volatile functions, nor any Vars of the
+ * table the index is for; use is_pseudo_constant_for_index() to check this.
+ * (Note: if the passed "node" is an OpExpr, the core planner already verified
+ * that the non-indexkey operand is pseudo-constant; but when the "node"
+ * is a FuncExpr, it does not check, since it doesn't know which of the
+ * function's arguments you might need to use in an index comparison value.)
+ *
+ * In many cases, an index condition can be generated but it is weaker than
+ * the function condition itself; for example, a LIKE with a constant prefix
+ * can produce an index range check based on the prefix, but we still need
+ * to execute the LIKE operator to verify the rest of the pattern.  We say
+ * that such an index condition is "lossy".  When returning an index condition,
+ * you should set the "lossy" request field to true if the condition is lossy,
+ * or false if it is an exact equivalent of the function's result.  The core
+ * code will initialize that field to true, which is the common case.
+ *
+ * It is important to verify that the index operator family is the correct
+ * one for the condition you want to generate.  Core support functions tend
+ * to use the known OID of a built-in opfamily for this, but extensions need
+ * to work harder, since their OIDs aren't fixed.  A possibly workable
+ * answer for an index on an extension datatype is to verify the index AM's
+ * OID instead, and then assume that there's only one relevant opclass for
+ * your datatype so the opfamily must be the right one.  Generating OpExpr
+ * nodes may also require knowing extension datatype OIDs (often you can
+ * find these out by applying exprType() to a function argument) and
+ * operator OIDs (which you can look up using get_opfamily_member).
+ */
+typedef struct SupportRequestIndexCondition
+{
+	NodeTag		type;
+
+	/* Input fields: */
+	struct PlannerInfo *root;	/* Planner's infrastructure */
+	Oid			funcid;			/* function we are inquiring about */
+	Node	   *node;			/* parse node invoking function */
+	int			indexarg;		/* index of function arg matching indexcol */
+	struct IndexOptInfo *index; /* planner's info about target index */
+	int			indexcol;		/* index of target index column (0-based) */
+	Oid			opfamily;		/* index column's operator family */
+	Oid			indexcollation; /* index column's collation */
+
+	/* Output fields: */
+	bool		lossy;			/* set to false if index condition is an exact
+								 * equivalent of the function call */
+} SupportRequestIndexCondition;
+
+#endif							/* SUPPORTNODES_H */
diff --git a/src/include/nodes/tidbitmap.h b/src/include/nodes/tidbitmap.h
new file mode 100644
index 0000000..d562fca
--- /dev/null
+++ b/src/include/nodes/tidbitmap.h
@@ -0,0 +1,75 @@
+/*-------------------------------------------------------------------------
+ *
+ * tidbitmap.h
+ *	  PostgreSQL tuple-id (TID) bitmap package
+ *
+ * This module provides bitmap data structures that are spiritually
+ * similar to Bitmapsets, but are specially adapted to store sets of
+ * tuple identifiers (TIDs), or ItemPointers.  In particular, the division
+ * of an ItemPointer into BlockNumber and OffsetNumber is catered for.
+ * Also, since we wish to be able to store very large tuple sets in
+ * memory with this data structure, we support "lossy" storage, in which
+ * we no longer remember individual tuple offsets on a page but only the
+ * fact that a particular page needs to be visited.
+ *
+ *
+ * Copyright (c) 2003-2020, PostgreSQL Global Development Group
+ *
+ * src/include/nodes/tidbitmap.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef TIDBITMAP_H
+#define TIDBITMAP_H
+
+#include "storage/itemptr.h"
+#include "utils/dsa.h"
+
+
+/*
+ * Actual bitmap representation is private to tidbitmap.c.  Callers can
+ * do IsA(x, TIDBitmap) on it, but nothing else.
+ */
+typedef struct TIDBitmap TIDBitmap;
+
+/* Likewise, TBMIterator is private */
+typedef struct TBMIterator TBMIterator;
+typedef struct TBMSharedIterator TBMSharedIterator;
+
+/* Result structure for tbm_iterate */
+typedef struct TBMIterateResult
+{
+	BlockNumber blockno;		/* page number containing tuples */
+	int			ntuples;		/* -1 indicates lossy result */
+	bool		recheck;		/* should the tuples be rechecked? */
+	/* Note: recheck is always true if ntuples < 0 */
+	OffsetNumber offsets[FLEXIBLE_ARRAY_MEMBER];
+} TBMIterateResult;
+
+/* function prototypes in nodes/tidbitmap.c */
+
+extern TIDBitmap *tbm_create(long maxbytes, dsa_area *dsa);
+extern void tbm_free(TIDBitmap *tbm);
+extern void tbm_free_shared_area(dsa_area *dsa, dsa_pointer dp);
+
+extern void tbm_add_tuples(TIDBitmap *tbm,
+						   const ItemPointer tids, int ntids,
+						   bool recheck);
+extern void tbm_add_page(TIDBitmap *tbm, BlockNumber pageno);
+
+extern void tbm_union(TIDBitmap *a, const TIDBitmap *b);
+extern void tbm_intersect(TIDBitmap *a, const TIDBitmap *b);
+
+extern bool tbm_is_empty(const TIDBitmap *tbm);
+
+extern TBMIterator *tbm_begin_iterate(TIDBitmap *tbm);
+extern dsa_pointer tbm_prepare_shared_iterate(TIDBitmap *tbm);
+extern TBMIterateResult *tbm_iterate(TBMIterator *iterator);
+extern TBMIterateResult *tbm_shared_iterate(TBMSharedIterator *iterator);
+extern void tbm_end_iterate(TBMIterator *iterator);
+extern void tbm_end_shared_iterate(TBMSharedIterator *iterator);
+extern TBMSharedIterator *tbm_attach_shared_iterate(dsa_area *dsa,
+													dsa_pointer dp);
+extern long tbm_calculate_entries(double maxbytes);
+
+#endif							/* TIDBITMAP_H */
diff --git a/src/include/nodes/value.h b/src/include/nodes/value.h
new file mode 100644
index 0000000..d4911b5
--- /dev/null
+++ b/src/include/nodes/value.h
@@ -0,0 +1,61 @@
+/*-------------------------------------------------------------------------
+ *
+ * value.h
+ *	  interface for Value nodes
+ *
+ *
+ * Copyright (c) 2003-2020, PostgreSQL Global Development Group
+ *
+ * src/include/nodes/value.h
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifndef VALUE_H
+#define VALUE_H
+
+#include "nodes/nodes.h"
+
+/*----------------------
+ *		Value node
+ *
+ * The same Value struct is used for five node types: T_Integer,
+ * T_Float, T_String, T_BitString, T_Null.
+ *
+ * Integral values are actually represented by a machine integer,
+ * but both floats and strings are represented as strings.
+ * Using T_Float as the node type simply indicates that
+ * the contents of the string look like a valid numeric literal.
+ *
+ * (Before Postgres 7.0, we used a double to represent T_Float,
+ * but that creates loss-of-precision problems when the value is
+ * ultimately destined to be converted to NUMERIC.  Since Value nodes
+ * are only used in the parsing process, not for runtime data, it's
+ * better to use the more general representation.)
+ *
+ * Note that an integer-looking string will get lexed as T_Float if
+ * the value is too large to fit in an 'int'.
+ *
+ * Nulls, of course, don't need the value part at all.
+ *----------------------
+ */
+typedef struct Value
+{
+	NodeTag		type;			/* tag appropriately (eg. T_String) */
+	union ValUnion
+	{
+		int			ival;		/* machine integer */
+		char	   *str;		/* string */
+	}			val;
+} Value;
+
+#define intVal(v)		(((Value *)(v))->val.ival)
+#define floatVal(v)		atof(((Value *)(v))->val.str)
+#define strVal(v)		(((Value *)(v))->val.str)
+
+extern Value *makeInteger(int i);
+extern Value *makeFloat(char *numericStr);
+extern Value *makeString(char *str);
+extern Value *makeBitString(char *str);
+
+#endif							/* VALUE_H */