Adding upstream version 16.2.upstream/16.2

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

1 files changed, 2398 insertions, 0 deletions

diff --git a/src/backend/executor/execPartition.c b/src/backend/executor/execPartition.c
new file mode 100644
index 0000000..f6c3432
--- /dev/null
+++ b/src/backend/executor/execPartition.c
@@ -0,0 +1,2398 @@
+/*-------------------------------------------------------------------------
+ *
+ * execPartition.c
+ *	  Support routines for partitioning.
+ *
+ * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ *	  src/backend/executor/execPartition.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "access/table.h"
+#include "access/tableam.h"
+#include "catalog/partition.h"
+#include "catalog/pg_inherits.h"
+#include "catalog/pg_type.h"
+#include "executor/execPartition.h"
+#include "executor/executor.h"
+#include "executor/nodeModifyTable.h"
+#include "foreign/fdwapi.h"
+#include "mb/pg_wchar.h"
+#include "miscadmin.h"
+#include "nodes/makefuncs.h"
+#include "partitioning/partbounds.h"
+#include "partitioning/partdesc.h"
+#include "partitioning/partprune.h"
+#include "rewrite/rewriteManip.h"
+#include "utils/acl.h"
+#include "utils/lsyscache.h"
+#include "utils/partcache.h"
+#include "utils/rls.h"
+#include "utils/ruleutils.h"
+
+
+/*-----------------------
+ * PartitionTupleRouting - Encapsulates all information required to
+ * route a tuple inserted into a partitioned table to one of its leaf
+ * partitions.
+ *
+ * partition_root
+ *		The partitioned table that's the target of the command.
+ *
+ * partition_dispatch_info
+ *		Array of 'max_dispatch' elements containing a pointer to a
+ *		PartitionDispatch object for every partitioned table touched by tuple
+ *		routing.  The entry for the target partitioned table is *always*
+ *		present in the 0th element of this array.  See comment for
+ *		PartitionDispatchData->indexes for details on how this array is
+ *		indexed.
+ *
+ * nonleaf_partitions
+ *		Array of 'max_dispatch' elements containing pointers to fake
+ *		ResultRelInfo objects for nonleaf partitions, useful for checking
+ *		the partition constraint.
+ *
+ * num_dispatch
+ *		The current number of items stored in the 'partition_dispatch_info'
+ *		array.  Also serves as the index of the next free array element for
+ *		new PartitionDispatch objects that need to be stored.
+ *
+ * max_dispatch
+ *		The current allocated size of the 'partition_dispatch_info' array.
+ *
+ * partitions
+ *		Array of 'max_partitions' elements containing a pointer to a
+ *		ResultRelInfo for every leaf partition touched by tuple routing.
+ *		Some of these are pointers to ResultRelInfos which are borrowed out of
+ *		the owning ModifyTableState node.  The remainder have been built
+ *		especially for tuple routing.  See comment for
+ *		PartitionDispatchData->indexes for details on how this array is
+ *		indexed.
+ *
+ * is_borrowed_rel
+ *		Array of 'max_partitions' booleans recording whether a given entry
+ *		in 'partitions' is a ResultRelInfo pointer borrowed from the owning
+ *		ModifyTableState node, rather than being built here.
+ *
+ * num_partitions
+ *		The current number of items stored in the 'partitions' array.  Also
+ *		serves as the index of the next free array element for new
+ *		ResultRelInfo objects that need to be stored.
+ *
+ * max_partitions
+ *		The current allocated size of the 'partitions' array.
+ *
+ * memcxt
+ *		Memory context used to allocate subsidiary structs.
+ *-----------------------
+ */
+struct PartitionTupleRouting
+{
+	Relation	partition_root;
+	PartitionDispatch *partition_dispatch_info;
+	ResultRelInfo **nonleaf_partitions;
+	int			num_dispatch;
+	int			max_dispatch;
+	ResultRelInfo **partitions;
+	bool	   *is_borrowed_rel;
+	int			num_partitions;
+	int			max_partitions;
+	MemoryContext memcxt;
+};
+
+/*-----------------------
+ * PartitionDispatch - information about one partitioned table in a partition
+ * hierarchy required to route a tuple to any of its partitions.  A
+ * PartitionDispatch is always encapsulated inside a PartitionTupleRouting
+ * struct and stored inside its 'partition_dispatch_info' array.
+ *
+ * reldesc
+ *		Relation descriptor of the table
+ *
+ * key
+ *		Partition key information of the table
+ *
+ * keystate
+ *		Execution state required for expressions in the partition key
+ *
+ * partdesc
+ *		Partition descriptor of the table
+ *
+ * tupslot
+ *		A standalone TupleTableSlot initialized with this table's tuple
+ *		descriptor, or NULL if no tuple conversion between the parent is
+ *		required.
+ *
+ * tupmap
+ *		TupleConversionMap to convert from the parent's rowtype to this table's
+ *		rowtype  (when extracting the partition key of a tuple just before
+ *		routing it through this table). A NULL value is stored if no tuple
+ *		conversion is required.
+ *
+ * indexes
+ *		Array of partdesc->nparts elements.  For leaf partitions the index
+ *		corresponds to the partition's ResultRelInfo in the encapsulating
+ *		PartitionTupleRouting's partitions array.  For partitioned partitions,
+ *		the index corresponds to the PartitionDispatch for it in its
+ *		partition_dispatch_info array.  -1 indicates we've not yet allocated
+ *		anything in PartitionTupleRouting for the partition.
+ *-----------------------
+ */
+typedef struct PartitionDispatchData
+{
+	Relation	reldesc;
+	PartitionKey key;
+	List	   *keystate;		/* list of ExprState */
+	PartitionDesc partdesc;
+	TupleTableSlot *tupslot;
+	AttrMap    *tupmap;
+	int			indexes[FLEXIBLE_ARRAY_MEMBER];
+}			PartitionDispatchData;
+
+
+static ResultRelInfo *ExecInitPartitionInfo(ModifyTableState *mtstate,
+											EState *estate, PartitionTupleRouting *proute,
+											PartitionDispatch dispatch,
+											ResultRelInfo *rootResultRelInfo,
+											int partidx);
+static void ExecInitRoutingInfo(ModifyTableState *mtstate,
+								EState *estate,
+								PartitionTupleRouting *proute,
+								PartitionDispatch dispatch,
+								ResultRelInfo *partRelInfo,
+								int partidx,
+								bool is_borrowed_rel);
+static PartitionDispatch ExecInitPartitionDispatchInfo(EState *estate,
+													   PartitionTupleRouting *proute,
+													   Oid partoid, PartitionDispatch parent_pd,
+													   int partidx, ResultRelInfo *rootResultRelInfo);
+static void FormPartitionKeyDatum(PartitionDispatch pd,
+								  TupleTableSlot *slot,
+								  EState *estate,
+								  Datum *values,
+								  bool *isnull);
+static int	get_partition_for_tuple(PartitionDispatch pd, Datum *values,
+									bool *isnull);
+static char *ExecBuildSlotPartitionKeyDescription(Relation rel,
+												  Datum *values,
+												  bool *isnull,
+												  int maxfieldlen);
+static List *adjust_partition_colnos(List *colnos, ResultRelInfo *leaf_part_rri);
+static List *adjust_partition_colnos_using_map(List *colnos, AttrMap *attrMap);
+static PartitionPruneState *CreatePartitionPruneState(PlanState *planstate,
+													  PartitionPruneInfo *pruneinfo);
+static void InitPartitionPruneContext(PartitionPruneContext *context,
+									  List *pruning_steps,
+									  PartitionDesc partdesc,
+									  PartitionKey partkey,
+									  PlanState *planstate,
+									  ExprContext *econtext);
+static void PartitionPruneFixSubPlanMap(PartitionPruneState *prunestate,
+										Bitmapset *initially_valid_subplans,
+										int n_total_subplans);
+static void find_matching_subplans_recurse(PartitionPruningData *prunedata,
+										   PartitionedRelPruningData *pprune,
+										   bool initial_prune,
+										   Bitmapset **validsubplans);
+
+
+/*
+ * ExecSetupPartitionTupleRouting - sets up information needed during
+ * tuple routing for partitioned tables, encapsulates it in
+ * PartitionTupleRouting, and returns it.
+ *
+ * Callers must use the returned PartitionTupleRouting during calls to
+ * ExecFindPartition().  The actual ResultRelInfo for a partition is only
+ * allocated when the partition is found for the first time.
+ *
+ * The current memory context is used to allocate this struct and all
+ * subsidiary structs that will be allocated from it later on.  Typically
+ * it should be estate->es_query_cxt.
+ */
+PartitionTupleRouting *
+ExecSetupPartitionTupleRouting(EState *estate, Relation rel)
+{
+	PartitionTupleRouting *proute;
+
+	/*
+	 * Here we attempt to expend as little effort as possible in setting up
+	 * the PartitionTupleRouting.  Each partition's ResultRelInfo is built on
+	 * demand, only when we actually need to route a tuple to that partition.
+	 * The reason for this is that a common case is for INSERT to insert a
+	 * single tuple into a partitioned table and this must be fast.
+	 */
+	proute = (PartitionTupleRouting *) palloc0(sizeof(PartitionTupleRouting));
+	proute->partition_root = rel;
+	proute->memcxt = CurrentMemoryContext;
+	/* Rest of members initialized by zeroing */
+
+	/*
+	 * Initialize this table's PartitionDispatch object.  Here we pass in the
+	 * parent as NULL as we don't need to care about any parent of the target
+	 * partitioned table.
+	 */
+	ExecInitPartitionDispatchInfo(estate, proute, RelationGetRelid(rel),
+								  NULL, 0, NULL);
+
+	return proute;
+}
+
+/*
+ * ExecFindPartition -- Return the ResultRelInfo for the leaf partition that
+ * the tuple contained in *slot should belong to.
+ *
+ * If the partition's ResultRelInfo does not yet exist in 'proute' then we set
+ * one up or reuse one from mtstate's resultRelInfo array.  When reusing a
+ * ResultRelInfo from the mtstate we verify that the relation is a valid
+ * target for INSERTs and initialize tuple routing information.
+ *
+ * rootResultRelInfo is the relation named in the query.
+ *
+ * estate must be non-NULL; we'll need it to compute any expressions in the
+ * partition keys.  Also, its per-tuple contexts are used as evaluation
+ * scratch space.
+ *
+ * If no leaf partition is found, this routine errors out with the appropriate
+ * error message.  An error may also be raised if the found target partition
+ * is not a valid target for an INSERT.
+ */
+ResultRelInfo *
+ExecFindPartition(ModifyTableState *mtstate,
+				  ResultRelInfo *rootResultRelInfo,
+				  PartitionTupleRouting *proute,
+				  TupleTableSlot *slot, EState *estate)
+{
+	PartitionDispatch *pd = proute->partition_dispatch_info;
+	Datum		values[PARTITION_MAX_KEYS];
+	bool		isnull[PARTITION_MAX_KEYS];
+	Relation	rel;
+	PartitionDispatch dispatch;
+	PartitionDesc partdesc;
+	ExprContext *ecxt = GetPerTupleExprContext(estate);
+	TupleTableSlot *ecxt_scantuple_saved = ecxt->ecxt_scantuple;
+	TupleTableSlot *rootslot = slot;
+	TupleTableSlot *myslot = NULL;
+	MemoryContext oldcxt;
+	ResultRelInfo *rri = NULL;
+
+	/* use per-tuple context here to avoid leaking memory */
+	oldcxt = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
+
+	/*
+	 * First check the root table's partition constraint, if any.  No point in
+	 * routing the tuple if it doesn't belong in the root table itself.
+	 */
+	if (rootResultRelInfo->ri_RelationDesc->rd_rel->relispartition)
+		ExecPartitionCheck(rootResultRelInfo, slot, estate, true);
+
+	/* start with the root partitioned table */
+	dispatch = pd[0];
+	while (dispatch != NULL)
+	{
+		int			partidx = -1;
+		bool		is_leaf;
+
+		CHECK_FOR_INTERRUPTS();
+
+		rel = dispatch->reldesc;
+		partdesc = dispatch->partdesc;
+
+		/*
+		 * Extract partition key from tuple. Expression evaluation machinery
+		 * that FormPartitionKeyDatum() invokes expects ecxt_scantuple to
+		 * point to the correct tuple slot.  The slot might have changed from
+		 * what was used for the parent table if the table of the current
+		 * partitioning level has different tuple descriptor from the parent.
+		 * So update ecxt_scantuple accordingly.
+		 */
+		ecxt->ecxt_scantuple = slot;
+		FormPartitionKeyDatum(dispatch, slot, estate, values, isnull);
+
+		/*
+		 * If this partitioned table has no partitions or no partition for
+		 * these values, error out.
+		 */
+		if (partdesc->nparts == 0 ||
+			(partidx = get_partition_for_tuple(dispatch, values, isnull)) < 0)
+		{
+			char	   *val_desc;
+
+			val_desc = ExecBuildSlotPartitionKeyDescription(rel,
+															values, isnull, 64);
+			Assert(OidIsValid(RelationGetRelid(rel)));
+			ereport(ERROR,
+					(errcode(ERRCODE_CHECK_VIOLATION),
+					 errmsg("no partition of relation \"%s\" found for row",
+							RelationGetRelationName(rel)),
+					 val_desc ?
+					 errdetail("Partition key of the failing row contains %s.",
+							   val_desc) : 0,
+					 errtable(rel)));
+		}
+
+		is_leaf = partdesc->is_leaf[partidx];
+		if (is_leaf)
+		{
+			/*
+			 * We've reached the leaf -- hurray, we're done.  Look to see if
+			 * we've already got a ResultRelInfo for this partition.
+			 */
+			if (likely(dispatch->indexes[partidx] >= 0))
+			{
+				/* ResultRelInfo already built */
+				Assert(dispatch->indexes[partidx] < proute->num_partitions);
+				rri = proute->partitions[dispatch->indexes[partidx]];
+			}
+			else
+			{
+				/*
+				 * If the partition is known in the owning ModifyTableState
+				 * node, we can re-use that ResultRelInfo instead of creating
+				 * a new one with ExecInitPartitionInfo().
+				 */
+				rri = ExecLookupResultRelByOid(mtstate,
+											   partdesc->oids[partidx],
+											   true, false);
+				if (rri)
+				{
+					/* Verify this ResultRelInfo allows INSERTs */
+					CheckValidResultRel(rri, CMD_INSERT);
+
+					/*
+					 * Initialize information needed to insert this and
+					 * subsequent tuples routed to this partition.
+					 */
+					ExecInitRoutingInfo(mtstate, estate, proute, dispatch,
+										rri, partidx, true);
+				}
+				else
+				{
+					/* We need to create a new one. */
+					rri = ExecInitPartitionInfo(mtstate, estate, proute,
+												dispatch,
+												rootResultRelInfo, partidx);
+				}
+			}
+			Assert(rri != NULL);
+
+			/* Signal to terminate the loop */
+			dispatch = NULL;
+		}
+		else
+		{
+			/*
+			 * Partition is a sub-partitioned table; get the PartitionDispatch
+			 */
+			if (likely(dispatch->indexes[partidx] >= 0))
+			{
+				/* Already built. */
+				Assert(dispatch->indexes[partidx] < proute->num_dispatch);
+
+				rri = proute->nonleaf_partitions[dispatch->indexes[partidx]];
+
+				/*
+				 * Move down to the next partition level and search again
+				 * until we find a leaf partition that matches this tuple
+				 */
+				dispatch = pd[dispatch->indexes[partidx]];
+			}
+			else
+			{
+				/* Not yet built. Do that now. */
+				PartitionDispatch subdispatch;
+
+				/*
+				 * Create the new PartitionDispatch.  We pass the current one
+				 * in as the parent PartitionDispatch
+				 */
+				subdispatch = ExecInitPartitionDispatchInfo(estate,
+															proute,
+															partdesc->oids[partidx],
+															dispatch, partidx,
+															mtstate->rootResultRelInfo);
+				Assert(dispatch->indexes[partidx] >= 0 &&
+					   dispatch->indexes[partidx] < proute->num_dispatch);
+
+				rri = proute->nonleaf_partitions[dispatch->indexes[partidx]];
+				dispatch = subdispatch;
+			}
+
+			/*
+			 * Convert the tuple to the new parent's layout, if different from
+			 * the previous parent.
+			 */
+			if (dispatch->tupslot)
+			{
+				AttrMap    *map = dispatch->tupmap;
+				TupleTableSlot *tempslot = myslot;
+
+				myslot = dispatch->tupslot;
+				slot = execute_attr_map_slot(map, slot, myslot);
+
+				if (tempslot != NULL)
+					ExecClearTuple(tempslot);
+			}
+		}
+
+		/*
+		 * If this partition is the default one, we must check its partition
+		 * constraint now, which may have changed concurrently due to
+		 * partitions being added to the parent.
+		 *
+		 * (We do this here, and do not rely on ExecInsert doing it, because
+		 * we don't want to miss doing it for non-leaf partitions.)
+		 */
+		if (partidx == partdesc->boundinfo->default_index)
+		{
+			/*
+			 * The tuple must match the partition's layout for the constraint
+			 * expression to be evaluated successfully.  If the partition is
+			 * sub-partitioned, that would already be the case due to the code
+			 * above, but for a leaf partition the tuple still matches the
+			 * parent's layout.
+			 *
+			 * Note that we have a map to convert from root to current
+			 * partition, but not from immediate parent to current partition.
+			 * So if we have to convert, do it from the root slot; if not, use
+			 * the root slot as-is.
+			 */
+			if (is_leaf)
+			{
+				TupleConversionMap *map = ExecGetRootToChildMap(rri, estate);
+
+				if (map)
+					slot = execute_attr_map_slot(map->attrMap, rootslot,
+												 rri->ri_PartitionTupleSlot);
+				else
+					slot = rootslot;
+			}
+
+			ExecPartitionCheck(rri, slot, estate, true);
+		}
+	}
+
+	/* Release the tuple in the lowest parent's dedicated slot. */
+	if (myslot != NULL)
+		ExecClearTuple(myslot);
+	/* and restore ecxt's scantuple */
+	ecxt->ecxt_scantuple = ecxt_scantuple_saved;
+	MemoryContextSwitchTo(oldcxt);
+
+	return rri;
+}
+
+/*
+ * ExecInitPartitionInfo
+ *		Lock the partition and initialize ResultRelInfo.  Also setup other
+ *		information for the partition and store it in the next empty slot in
+ *		the proute->partitions array.
+ *
+ * Returns the ResultRelInfo
+ */
+static ResultRelInfo *
+ExecInitPartitionInfo(ModifyTableState *mtstate, EState *estate,
+					  PartitionTupleRouting *proute,
+					  PartitionDispatch dispatch,
+					  ResultRelInfo *rootResultRelInfo,
+					  int partidx)
+{
+	ModifyTable *node = (ModifyTable *) mtstate->ps.plan;
+	Oid			partOid = dispatch->partdesc->oids[partidx];
+	Relation	partrel;
+	int			firstVarno = mtstate->resultRelInfo[0].ri_RangeTableIndex;
+	Relation	firstResultRel = mtstate->resultRelInfo[0].ri_RelationDesc;
+	ResultRelInfo *leaf_part_rri;
+	MemoryContext oldcxt;
+	AttrMap    *part_attmap = NULL;
+	bool		found_whole_row;
+
+	oldcxt = MemoryContextSwitchTo(proute->memcxt);
+
+	partrel = table_open(partOid, RowExclusiveLock);
+
+	leaf_part_rri = makeNode(ResultRelInfo);
+	InitResultRelInfo(leaf_part_rri,
+					  partrel,
+					  0,
+					  rootResultRelInfo,
+					  estate->es_instrument);
+
+	/*
+	 * Verify result relation is a valid target for an INSERT.  An UPDATE of a
+	 * partition-key becomes a DELETE+INSERT operation, so this check is still
+	 * required when the operation is CMD_UPDATE.
+	 */
+	CheckValidResultRel(leaf_part_rri, CMD_INSERT);
+
+	/*
+	 * Open partition indices.  The user may have asked to check for conflicts
+	 * within this leaf partition and do "nothing" instead of throwing an
+	 * error.  Be prepared in that case by initializing the index information
+	 * needed by ExecInsert() to perform speculative insertions.
+	 */
+	if (partrel->rd_rel->relhasindex &&
+		leaf_part_rri->ri_IndexRelationDescs == NULL)
+		ExecOpenIndices(leaf_part_rri,
+						(node != NULL &&
+						 node->onConflictAction != ONCONFLICT_NONE));
+
+	/*
+	 * Build WITH CHECK OPTION constraints for the partition.  Note that we
+	 * didn't build the withCheckOptionList for partitions within the planner,
+	 * but simple translation of varattnos will suffice.  This only occurs for
+	 * the INSERT case or in the case of UPDATE/MERGE tuple routing where we
+	 * didn't find a result rel to reuse.
+	 */
+	if (node && node->withCheckOptionLists != NIL)
+	{
+		List	   *wcoList;
+		List	   *wcoExprs = NIL;
+		ListCell   *ll;
+
+		/*
+		 * In the case of INSERT on a partitioned table, there is only one
+		 * plan.  Likewise, there is only one WCO list, not one per partition.
+		 * For UPDATE/MERGE, there are as many WCO lists as there are plans.
+		 */
+		Assert((node->operation == CMD_INSERT &&
+				list_length(node->withCheckOptionLists) == 1 &&
+				list_length(node->resultRelations) == 1) ||
+			   (node->operation == CMD_UPDATE &&
+				list_length(node->withCheckOptionLists) ==
+				list_length(node->resultRelations)) ||
+			   (node->operation == CMD_MERGE &&
+				list_length(node->withCheckOptionLists) ==
+				list_length(node->resultRelations)));
+
+		/*
+		 * Use the WCO list of the first plan as a reference to calculate
+		 * attno's for the WCO list of this partition.  In the INSERT case,
+		 * that refers to the root partitioned table, whereas in the UPDATE
+		 * tuple routing case, that refers to the first partition in the
+		 * mtstate->resultRelInfo array.  In any case, both that relation and
+		 * this partition should have the same columns, so we should be able
+		 * to map attributes successfully.
+		 */
+		wcoList = linitial(node->withCheckOptionLists);
+
+		/*
+		 * Convert Vars in it to contain this partition's attribute numbers.
+		 */
+		part_attmap =
+			build_attrmap_by_name(RelationGetDescr(partrel),
+								  RelationGetDescr(firstResultRel),
+								  false);
+		wcoList = (List *)
+			map_variable_attnos((Node *) wcoList,
+								firstVarno, 0,
+								part_attmap,
+								RelationGetForm(partrel)->reltype,
+								&found_whole_row);
+		/* We ignore the value of found_whole_row. */
+
+		foreach(ll, wcoList)
+		{
+			WithCheckOption *wco = lfirst_node(WithCheckOption, ll);
+			ExprState  *wcoExpr = ExecInitQual(castNode(List, wco->qual),
+											   &mtstate->ps);
+
+			wcoExprs = lappend(wcoExprs, wcoExpr);
+		}
+
+		leaf_part_rri->ri_WithCheckOptions = wcoList;
+		leaf_part_rri->ri_WithCheckOptionExprs = wcoExprs;
+	}
+
+	/*
+	 * Build the RETURNING projection for the partition.  Note that we didn't
+	 * build the returningList for partitions within the planner, but simple
+	 * translation of varattnos will suffice.  This only occurs for the INSERT
+	 * case or in the case of UPDATE tuple routing where we didn't find a
+	 * result rel to reuse.
+	 */
+	if (node && node->returningLists != NIL)
+	{
+		TupleTableSlot *slot;
+		ExprContext *econtext;
+		List	   *returningList;
+
+		/* See the comment above for WCO lists. */
+		/* (except no RETURNING support for MERGE yet) */
+		Assert((node->operation == CMD_INSERT &&
+				list_length(node->returningLists) == 1 &&
+				list_length(node->resultRelations) == 1) ||
+			   (node->operation == CMD_UPDATE &&
+				list_length(node->returningLists) ==
+				list_length(node->resultRelations)));
+
+		/*
+		 * Use the RETURNING list of the first plan as a reference to
+		 * calculate attno's for the RETURNING list of this partition.  See
+		 * the comment above for WCO lists for more details on why this is
+		 * okay.
+		 */
+		returningList = linitial(node->returningLists);
+
+		/*
+		 * Convert Vars in it to contain this partition's attribute numbers.
+		 */
+		if (part_attmap == NULL)
+			part_attmap =
+				build_attrmap_by_name(RelationGetDescr(partrel),
+									  RelationGetDescr(firstResultRel),
+									  false);
+		returningList = (List *)
+			map_variable_attnos((Node *) returningList,
+								firstVarno, 0,
+								part_attmap,
+								RelationGetForm(partrel)->reltype,
+								&found_whole_row);
+		/* We ignore the value of found_whole_row. */
+
+		leaf_part_rri->ri_returningList = returningList;
+
+		/*
+		 * Initialize the projection itself.
+		 *
+		 * Use the slot and the expression context that would have been set up
+		 * in ExecInitModifyTable() for projection's output.
+		 */
+		Assert(mtstate->ps.ps_ResultTupleSlot != NULL);
+		slot = mtstate->ps.ps_ResultTupleSlot;
+		Assert(mtstate->ps.ps_ExprContext != NULL);
+		econtext = mtstate->ps.ps_ExprContext;
+		leaf_part_rri->ri_projectReturning =
+			ExecBuildProjectionInfo(returningList, econtext, slot,
+									&mtstate->ps, RelationGetDescr(partrel));
+	}
+
+	/* Set up information needed for routing tuples to the partition. */
+	ExecInitRoutingInfo(mtstate, estate, proute, dispatch,
+						leaf_part_rri, partidx, false);
+
+	/*
+	 * If there is an ON CONFLICT clause, initialize state for it.
+	 */
+	if (node && node->onConflictAction != ONCONFLICT_NONE)
+	{
+		TupleDesc	partrelDesc = RelationGetDescr(partrel);
+		ExprContext *econtext = mtstate->ps.ps_ExprContext;
+		ListCell   *lc;
+		List	   *arbiterIndexes = NIL;
+
+		/*
+		 * If there is a list of arbiter indexes, map it to a list of indexes
+		 * in the partition.  We do that by scanning the partition's index
+		 * list and searching for ancestry relationships to each index in the
+		 * ancestor table.
+		 */
+		if (rootResultRelInfo->ri_onConflictArbiterIndexes != NIL)
+		{
+			List	   *childIdxs;
+
+			childIdxs = RelationGetIndexList(leaf_part_rri->ri_RelationDesc);
+
+			foreach(lc, childIdxs)
+			{
+				Oid			childIdx = lfirst_oid(lc);
+				List	   *ancestors;
+				ListCell   *lc2;
+
+				ancestors = get_partition_ancestors(childIdx);
+				foreach(lc2, rootResultRelInfo->ri_onConflictArbiterIndexes)
+				{
+					if (list_member_oid(ancestors, lfirst_oid(lc2)))
+						arbiterIndexes = lappend_oid(arbiterIndexes, childIdx);
+				}
+				list_free(ancestors);
+			}
+		}
+
+		/*
+		 * If the resulting lists are of inequal length, something is wrong.
+		 * (This shouldn't happen, since arbiter index selection should not
+		 * pick up an invalid index.)
+		 */
+		if (list_length(rootResultRelInfo->ri_onConflictArbiterIndexes) !=
+			list_length(arbiterIndexes))
+			elog(ERROR, "invalid arbiter index list");
+		leaf_part_rri->ri_onConflictArbiterIndexes = arbiterIndexes;
+
+		/*
+		 * In the DO UPDATE case, we have some more state to initialize.
+		 */
+		if (node->onConflictAction == ONCONFLICT_UPDATE)
+		{
+			OnConflictSetState *onconfl = makeNode(OnConflictSetState);
+			TupleConversionMap *map;
+
+			map = ExecGetRootToChildMap(leaf_part_rri, estate);
+
+			Assert(node->onConflictSet != NIL);
+			Assert(rootResultRelInfo->ri_onConflict != NULL);
+
+			leaf_part_rri->ri_onConflict = onconfl;
+
+			/*
+			 * Need a separate existing slot for each partition, as the
+			 * partition could be of a different AM, even if the tuple
+			 * descriptors match.
+			 */
+			onconfl->oc_Existing =
+				table_slot_create(leaf_part_rri->ri_RelationDesc,
+								  &mtstate->ps.state->es_tupleTable);
+
+			/*
+			 * If the partition's tuple descriptor matches exactly the root
+			 * parent (the common case), we can re-use most of the parent's ON
+			 * CONFLICT SET state, skipping a bunch of work.  Otherwise, we
+			 * need to create state specific to this partition.
+			 */
+			if (map == NULL)
+			{
+				/*
+				 * It's safe to reuse these from the partition root, as we
+				 * only process one tuple at a time (therefore we won't
+				 * overwrite needed data in slots), and the results of
+				 * projections are independent of the underlying storage.
+				 * Projections and where clauses themselves don't store state
+				 * / are independent of the underlying storage.
+				 */
+				onconfl->oc_ProjSlot =
+					rootResultRelInfo->ri_onConflict->oc_ProjSlot;
+				onconfl->oc_ProjInfo =
+					rootResultRelInfo->ri_onConflict->oc_ProjInfo;
+				onconfl->oc_WhereClause =
+					rootResultRelInfo->ri_onConflict->oc_WhereClause;
+			}
+			else
+			{
+				List	   *onconflset;
+				List	   *onconflcols;
+
+				/*
+				 * Translate expressions in onConflictSet to account for
+				 * different attribute numbers.  For that, map partition
+				 * varattnos twice: first to catch the EXCLUDED
+				 * pseudo-relation (INNER_VAR), and second to handle the main
+				 * target relation (firstVarno).
+				 */
+				onconflset = copyObject(node->onConflictSet);
+				if (part_attmap == NULL)
+					part_attmap =
+						build_attrmap_by_name(RelationGetDescr(partrel),
+											  RelationGetDescr(firstResultRel),
+											  false);
+				onconflset = (List *)
+					map_variable_attnos((Node *) onconflset,
+										INNER_VAR, 0,
+										part_attmap,
+										RelationGetForm(partrel)->reltype,
+										&found_whole_row);
+				/* We ignore the value of found_whole_row. */
+				onconflset = (List *)
+					map_variable_attnos((Node *) onconflset,
+										firstVarno, 0,
+										part_attmap,
+										RelationGetForm(partrel)->reltype,
+										&found_whole_row);
+				/* We ignore the value of found_whole_row. */
+
+				/* Finally, adjust the target colnos to match the partition. */
+				onconflcols = adjust_partition_colnos(node->onConflictCols,
+													  leaf_part_rri);
+
+				/* create the tuple slot for the UPDATE SET projection */
+				onconfl->oc_ProjSlot =
+					table_slot_create(partrel,
+									  &mtstate->ps.state->es_tupleTable);
+
+				/* build UPDATE SET projection state */
+				onconfl->oc_ProjInfo =
+					ExecBuildUpdateProjection(onconflset,
+											  true,
+											  onconflcols,
+											  partrelDesc,
+											  econtext,
+											  onconfl->oc_ProjSlot,
+											  &mtstate->ps);
+
+				/*
+				 * If there is a WHERE clause, initialize state where it will
+				 * be evaluated, mapping the attribute numbers appropriately.
+				 * As with onConflictSet, we need to map partition varattnos
+				 * to the partition's tupdesc.
+				 */
+				if (node->onConflictWhere)
+				{
+					List	   *clause;
+
+					clause = copyObject((List *) node->onConflictWhere);
+					clause = (List *)
+						map_variable_attnos((Node *) clause,
+											INNER_VAR, 0,
+											part_attmap,
+											RelationGetForm(partrel)->reltype,
+											&found_whole_row);
+					/* We ignore the value of found_whole_row. */
+					clause = (List *)
+						map_variable_attnos((Node *) clause,
+											firstVarno, 0,
+											part_attmap,
+											RelationGetForm(partrel)->reltype,
+											&found_whole_row);
+					/* We ignore the value of found_whole_row. */
+					onconfl->oc_WhereClause =
+						ExecInitQual((List *) clause, &mtstate->ps);
+				}
+			}
+		}
+	}
+
+	/*
+	 * Since we've just initialized this ResultRelInfo, it's not in any list
+	 * attached to the estate as yet.  Add it, so that it can be found later.
+	 *
+	 * Note that the entries in this list appear in no predetermined order,
+	 * because partition result rels are initialized as and when they're
+	 * needed.
+	 */
+	MemoryContextSwitchTo(estate->es_query_cxt);
+	estate->es_tuple_routing_result_relations =
+		lappend(estate->es_tuple_routing_result_relations,
+				leaf_part_rri);
+
+	/*
+	 * Initialize information about this partition that's needed to handle
+	 * MERGE.  We take the "first" result relation's mergeActionList as
+	 * reference and make copy for this relation, converting stuff that
+	 * references attribute numbers to match this relation's.
+	 *
+	 * This duplicates much of the logic in ExecInitMerge(), so something
+	 * changes there, look here too.
+	 */
+	if (node && node->operation == CMD_MERGE)
+	{
+		List	   *firstMergeActionList = linitial(node->mergeActionLists);
+		ListCell   *lc;
+		ExprContext *econtext = mtstate->ps.ps_ExprContext;
+
+		if (part_attmap == NULL)
+			part_attmap =
+				build_attrmap_by_name(RelationGetDescr(partrel),
+									  RelationGetDescr(firstResultRel),
+									  false);
+
+		if (unlikely(!leaf_part_rri->ri_projectNewInfoValid))
+			ExecInitMergeTupleSlots(mtstate, leaf_part_rri);
+
+		foreach(lc, firstMergeActionList)
+		{
+			/* Make a copy for this relation to be safe.  */
+			MergeAction *action = copyObject(lfirst(lc));
+			MergeActionState *action_state;
+			List	  **list;
+
+			/* Generate the action's state for this relation */
+			action_state = makeNode(MergeActionState);
+			action_state->mas_action = action;
+
+			/* And put the action in the appropriate list */
+			if (action->matched)
+				list = &leaf_part_rri->ri_matchedMergeAction;
+			else
+				list = &leaf_part_rri->ri_notMatchedMergeAction;
+			*list = lappend(*list, action_state);
+
+			switch (action->commandType)
+			{
+				case CMD_INSERT:
+
+					/*
+					 * ExecCheckPlanOutput() already done on the targetlist
+					 * when "first" result relation initialized and it is same
+					 * for all result relations.
+					 */
+					action_state->mas_proj =
+						ExecBuildProjectionInfo(action->targetList, econtext,
+												leaf_part_rri->ri_newTupleSlot,
+												&mtstate->ps,
+												RelationGetDescr(partrel));
+					break;
+				case CMD_UPDATE:
+
+					/*
+					 * Convert updateColnos from "first" result relation
+					 * attribute numbers to this result rel's.
+					 */
+					if (part_attmap)
+						action->updateColnos =
+							adjust_partition_colnos_using_map(action->updateColnos,
+															  part_attmap);
+					action_state->mas_proj =
+						ExecBuildUpdateProjection(action->targetList,
+												  true,
+												  action->updateColnos,
+												  RelationGetDescr(leaf_part_rri->ri_RelationDesc),
+												  econtext,
+												  leaf_part_rri->ri_newTupleSlot,
+												  NULL);
+					break;
+				case CMD_DELETE:
+					break;
+
+				default:
+					elog(ERROR, "unknown action in MERGE WHEN clause");
+			}
+
+			/* found_whole_row intentionally ignored. */
+			action->qual =
+				map_variable_attnos(action->qual,
+									firstVarno, 0,
+									part_attmap,
+									RelationGetForm(partrel)->reltype,
+									&found_whole_row);
+			action_state->mas_whenqual =
+				ExecInitQual((List *) action->qual, &mtstate->ps);
+		}
+	}
+	MemoryContextSwitchTo(oldcxt);
+
+	return leaf_part_rri;
+}
+
+/*
+ * ExecInitRoutingInfo
+ *		Set up information needed for translating tuples between root
+ *		partitioned table format and partition format, and keep track of it
+ *		in PartitionTupleRouting.
+ */
+static void
+ExecInitRoutingInfo(ModifyTableState *mtstate,
+					EState *estate,
+					PartitionTupleRouting *proute,
+					PartitionDispatch dispatch,
+					ResultRelInfo *partRelInfo,
+					int partidx,
+					bool is_borrowed_rel)
+{
+	MemoryContext oldcxt;
+	int			rri_index;
+
+	oldcxt = MemoryContextSwitchTo(proute->memcxt);
+
+	/*
+	 * Set up tuple conversion between root parent and the partition if the
+	 * two have different rowtypes.  If conversion is indeed required, also
+	 * initialize a slot dedicated to storing this partition's converted
+	 * tuples.  Various operations that are applied to tuples after routing,
+	 * such as checking constraints, will refer to this slot.
+	 */
+	if (ExecGetRootToChildMap(partRelInfo, estate) != NULL)
+	{
+		Relation	partrel = partRelInfo->ri_RelationDesc;
+
+		/*
+		 * This pins the partition's TupleDesc, which will be released at the
+		 * end of the command.
+		 */
+		partRelInfo->ri_PartitionTupleSlot =
+			table_slot_create(partrel, &estate->es_tupleTable);
+	}
+	else
+		partRelInfo->ri_PartitionTupleSlot = NULL;
+
+	/*
+	 * If the partition is a foreign table, let the FDW init itself for
+	 * routing tuples to the partition.
+	 */
+	if (partRelInfo->ri_FdwRoutine != NULL &&
+		partRelInfo->ri_FdwRoutine->BeginForeignInsert != NULL)
+		partRelInfo->ri_FdwRoutine->BeginForeignInsert(mtstate, partRelInfo);
+
+	/*
+	 * Determine if the FDW supports batch insert and determine the batch size
+	 * (a FDW may support batching, but it may be disabled for the
+	 * server/table or for this particular query).
+	 *
+	 * If the FDW does not support batching, we set the batch size to 1.
+	 */
+	if (partRelInfo->ri_FdwRoutine != NULL &&
+		partRelInfo->ri_FdwRoutine->GetForeignModifyBatchSize &&
+		partRelInfo->ri_FdwRoutine->ExecForeignBatchInsert)
+		partRelInfo->ri_BatchSize =
+			partRelInfo->ri_FdwRoutine->GetForeignModifyBatchSize(partRelInfo);
+	else
+		partRelInfo->ri_BatchSize = 1;
+
+	Assert(partRelInfo->ri_BatchSize >= 1);
+
+	partRelInfo->ri_CopyMultiInsertBuffer = NULL;
+
+	/*
+	 * Keep track of it in the PartitionTupleRouting->partitions array.
+	 */
+	Assert(dispatch->indexes[partidx] == -1);
+
+	rri_index = proute->num_partitions++;
+
+	/* Allocate or enlarge the array, as needed */
+	if (proute->num_partitions >= proute->max_partitions)
+	{
+		if (proute->max_partitions == 0)
+		{
+			proute->max_partitions = 8;
+			proute->partitions = (ResultRelInfo **)
+				palloc(sizeof(ResultRelInfo *) * proute->max_partitions);
+			proute->is_borrowed_rel = (bool *)
+				palloc(sizeof(bool) * proute->max_partitions);
+		}
+		else
+		{
+			proute->max_partitions *= 2;
+			proute->partitions = (ResultRelInfo **)
+				repalloc(proute->partitions, sizeof(ResultRelInfo *) *
+						 proute->max_partitions);
+			proute->is_borrowed_rel = (bool *)
+				repalloc(proute->is_borrowed_rel, sizeof(bool) *
+						 proute->max_partitions);
+		}
+	}
+
+	proute->partitions[rri_index] = partRelInfo;
+	proute->is_borrowed_rel[rri_index] = is_borrowed_rel;
+	dispatch->indexes[partidx] = rri_index;
+
+	MemoryContextSwitchTo(oldcxt);
+}
+
+/*
+ * ExecInitPartitionDispatchInfo
+ *		Lock the partitioned table (if not locked already) and initialize
+ *		PartitionDispatch for a partitioned table and store it in the next
+ *		available slot in the proute->partition_dispatch_info array.  Also,
+ *		record the index into this array in the parent_pd->indexes[] array in
+ *		the partidx element so that we can properly retrieve the newly created
+ *		PartitionDispatch later.
+ */
+static PartitionDispatch
+ExecInitPartitionDispatchInfo(EState *estate,
+							  PartitionTupleRouting *proute, Oid partoid,
+							  PartitionDispatch parent_pd, int partidx,
+							  ResultRelInfo *rootResultRelInfo)
+{
+	Relation	rel;
+	PartitionDesc partdesc;
+	PartitionDispatch pd;
+	int			dispatchidx;
+	MemoryContext oldcxt;
+
+	/*
+	 * For data modification, it is better that executor does not include
+	 * partitions being detached, except when running in snapshot-isolation
+	 * mode.  This means that a read-committed transaction immediately gets a
+	 * "no partition for tuple" error when a tuple is inserted into a
+	 * partition that's being detached concurrently, but a transaction in
+	 * repeatable-read mode can still use such a partition.
+	 */
+	if (estate->es_partition_directory == NULL)
+		estate->es_partition_directory =
+			CreatePartitionDirectory(estate->es_query_cxt,
+									 !IsolationUsesXactSnapshot());
+
+	oldcxt = MemoryContextSwitchTo(proute->memcxt);
+
+	/*
+	 * Only sub-partitioned tables need to be locked here.  The root
+	 * partitioned table will already have been locked as it's referenced in
+	 * the query's rtable.
+	 */
+	if (partoid != RelationGetRelid(proute->partition_root))
+		rel = table_open(partoid, RowExclusiveLock);
+	else
+		rel = proute->partition_root;
+	partdesc = PartitionDirectoryLookup(estate->es_partition_directory, rel);
+
+	pd = (PartitionDispatch) palloc(offsetof(PartitionDispatchData, indexes) +
+									partdesc->nparts * sizeof(int));
+	pd->reldesc = rel;
+	pd->key = RelationGetPartitionKey(rel);
+	pd->keystate = NIL;
+	pd->partdesc = partdesc;
+	if (parent_pd != NULL)
+	{
+		TupleDesc	tupdesc = RelationGetDescr(rel);
+
+		/*
+		 * For sub-partitioned tables where the column order differs from its
+		 * direct parent partitioned table, we must store a tuple table slot
+		 * initialized with its tuple descriptor and a tuple conversion map to
+		 * convert a tuple from its parent's rowtype to its own.  This is to
+		 * make sure that we are looking at the correct row using the correct
+		 * tuple descriptor when computing its partition key for tuple
+		 * routing.
+		 */
+		pd->tupmap = build_attrmap_by_name_if_req(RelationGetDescr(parent_pd->reldesc),
+												  tupdesc,
+												  false);
+		pd->tupslot = pd->tupmap ?
+			MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual) : NULL;
+	}
+	else
+	{
+		/* Not required for the root partitioned table */
+		pd->tupmap = NULL;
+		pd->tupslot = NULL;
+	}
+
+	/*
+	 * Initialize with -1 to signify that the corresponding partition's
+	 * ResultRelInfo or PartitionDispatch has not been created yet.
+	 */
+	memset(pd->indexes, -1, sizeof(int) * partdesc->nparts);
+
+	/* Track in PartitionTupleRouting for later use */
+	dispatchidx = proute->num_dispatch++;
+
+	/* Allocate or enlarge the array, as needed */
+	if (proute->num_dispatch >= proute->max_dispatch)
+	{
+		if (proute->max_dispatch == 0)
+		{
+			proute->max_dispatch = 4;
+			proute->partition_dispatch_info = (PartitionDispatch *)
+				palloc(sizeof(PartitionDispatch) * proute->max_dispatch);
+			proute->nonleaf_partitions = (ResultRelInfo **)
+				palloc(sizeof(ResultRelInfo *) * proute->max_dispatch);
+		}
+		else
+		{
+			proute->max_dispatch *= 2;
+			proute->partition_dispatch_info = (PartitionDispatch *)
+				repalloc(proute->partition_dispatch_info,
+						 sizeof(PartitionDispatch) * proute->max_dispatch);
+			proute->nonleaf_partitions = (ResultRelInfo **)
+				repalloc(proute->nonleaf_partitions,
+						 sizeof(ResultRelInfo *) * proute->max_dispatch);
+		}
+	}
+	proute->partition_dispatch_info[dispatchidx] = pd;
+
+	/*
+	 * If setting up a PartitionDispatch for a sub-partitioned table, we may
+	 * also need a minimally valid ResultRelInfo for checking the partition
+	 * constraint later; set that up now.
+	 */
+	if (parent_pd)
+	{
+		ResultRelInfo *rri = makeNode(ResultRelInfo);
+
+		InitResultRelInfo(rri, rel, 0, rootResultRelInfo, 0);
+		proute->nonleaf_partitions[dispatchidx] = rri;
+	}
+	else
+		proute->nonleaf_partitions[dispatchidx] = NULL;
+
+	/*
+	 * Finally, if setting up a PartitionDispatch for a sub-partitioned table,
+	 * install a downlink in the parent to allow quick descent.
+	 */
+	if (parent_pd)
+	{
+		Assert(parent_pd->indexes[partidx] == -1);
+		parent_pd->indexes[partidx] = dispatchidx;
+	}
+
+	MemoryContextSwitchTo(oldcxt);
+
+	return pd;
+}
+
+/*
+ * ExecCleanupTupleRouting -- Clean up objects allocated for partition tuple
+ * routing.
+ *
+ * Close all the partitioned tables, leaf partitions, and their indices.
+ */
+void
+ExecCleanupTupleRouting(ModifyTableState *mtstate,
+						PartitionTupleRouting *proute)
+{
+	int			i;
+
+	/*
+	 * Remember, proute->partition_dispatch_info[0] corresponds to the root
+	 * partitioned table, which we must not try to close, because it is the
+	 * main target table of the query that will be closed by callers such as
+	 * ExecEndPlan() or DoCopy(). Also, tupslot is NULL for the root
+	 * partitioned table.
+	 */
+	for (i = 1; i < proute->num_dispatch; i++)
+	{
+		PartitionDispatch pd = proute->partition_dispatch_info[i];
+
+		table_close(pd->reldesc, NoLock);
+
+		if (pd->tupslot)
+			ExecDropSingleTupleTableSlot(pd->tupslot);
+	}
+
+	for (i = 0; i < proute->num_partitions; i++)
+	{
+		ResultRelInfo *resultRelInfo = proute->partitions[i];
+
+		/* Allow any FDWs to shut down */
+		if (resultRelInfo->ri_FdwRoutine != NULL &&
+			resultRelInfo->ri_FdwRoutine->EndForeignInsert != NULL)
+			resultRelInfo->ri_FdwRoutine->EndForeignInsert(mtstate->ps.state,
+														   resultRelInfo);
+
+		/*
+		 * Close it if it's not one of the result relations borrowed from the
+		 * owning ModifyTableState; those will be closed by ExecEndPlan().
+		 */
+		if (proute->is_borrowed_rel[i])
+			continue;
+
+		ExecCloseIndices(resultRelInfo);
+		table_close(resultRelInfo->ri_RelationDesc, NoLock);
+	}
+}
+
+/* ----------------
+ *		FormPartitionKeyDatum
+ *			Construct values[] and isnull[] arrays for the partition key
+ *			of a tuple.
+ *
+ *	pd				Partition dispatch object of the partitioned table
+ *	slot			Heap tuple from which to extract partition key
+ *	estate			executor state for evaluating any partition key
+ *					expressions (must be non-NULL)
+ *	values			Array of partition key Datums (output area)
+ *	isnull			Array of is-null indicators (output area)
+ *
+ * the ecxt_scantuple slot of estate's per-tuple expr context must point to
+ * the heap tuple passed in.
+ * ----------------
+ */
+static void
+FormPartitionKeyDatum(PartitionDispatch pd,
+					  TupleTableSlot *slot,
+					  EState *estate,
+					  Datum *values,
+					  bool *isnull)
+{
+	ListCell   *partexpr_item;
+	int			i;
+
+	if (pd->key->partexprs != NIL && pd->keystate == NIL)
+	{
+		/* Check caller has set up context correctly */
+		Assert(estate != NULL &&
+			   GetPerTupleExprContext(estate)->ecxt_scantuple == slot);
+
+		/* First time through, set up expression evaluation state */
+		pd->keystate = ExecPrepareExprList(pd->key->partexprs, estate);
+	}
+
+	partexpr_item = list_head(pd->keystate);
+	for (i = 0; i < pd->key->partnatts; i++)
+	{
+		AttrNumber	keycol = pd->key->partattrs[i];
+		Datum		datum;
+		bool		isNull;
+
+		if (keycol != 0)
+		{
+			/* Plain column; get the value directly from the heap tuple */
+			datum = slot_getattr(slot, keycol, &isNull);
+		}
+		else
+		{
+			/* Expression; need to evaluate it */
+			if (partexpr_item == NULL)
+				elog(ERROR, "wrong number of partition key expressions");
+			datum = ExecEvalExprSwitchContext((ExprState *) lfirst(partexpr_item),
+											  GetPerTupleExprContext(estate),
+											  &isNull);
+			partexpr_item = lnext(pd->keystate, partexpr_item);
+		}
+		values[i] = datum;
+		isnull[i] = isNull;
+	}
+
+	if (partexpr_item != NULL)
+		elog(ERROR, "wrong number of partition key expressions");
+}
+
+/*
+ * The number of times the same partition must be found in a row before we
+ * switch from a binary search for the given values to just checking if the
+ * values belong to the last found partition.  This must be above 0.
+ */
+#define PARTITION_CACHED_FIND_THRESHOLD			16
+
+/*
+ * get_partition_for_tuple
+ *		Finds partition of relation which accepts the partition key specified
+ *		in values and isnull.
+ *
+ * Calling this function can be quite expensive when LIST and RANGE
+ * partitioned tables have many partitions.  This is due to the binary search
+ * that's done to find the correct partition.  Many of the use cases for LIST
+ * and RANGE partitioned tables make it likely that the same partition is
+ * found in subsequent ExecFindPartition() calls.  This is especially true for
+ * cases such as RANGE partitioned tables on a TIMESTAMP column where the
+ * partition key is the current time.  When asked to find a partition for a
+ * RANGE or LIST partitioned table, we record the partition index and datum
+ * offset we've found for the given 'values' in the PartitionDesc (which is
+ * stored in relcache), and if we keep finding the same partition
+ * PARTITION_CACHED_FIND_THRESHOLD times in a row, then we'll enable caching
+ * logic and instead of performing a binary search to find the correct
+ * partition, we'll just double-check that 'values' still belong to the last
+ * found partition, and if so, we'll return that partition index, thus
+ * skipping the need for the binary search.  If we fail to match the last
+ * partition when double checking, then we fall back on doing a binary search.
+ * In this case, unless we find 'values' belong to the DEFAULT partition,
+ * we'll reset the number of times we've hit the same partition so that we
+ * don't attempt to use the cache again until we've found that partition at
+ * least PARTITION_CACHED_FIND_THRESHOLD times in a row.
+ *
+ * For cases where the partition changes on each lookup, the amount of
+ * additional work required just amounts to recording the last found partition
+ * and bound offset then resetting the found counter.  This is cheap and does
+ * not appear to cause any meaningful slowdowns for such cases.
+ *
+ * No caching of partitions is done when the last found partition is the
+ * DEFAULT or NULL partition.  For the case of the DEFAULT partition, there
+ * is no bound offset storing the matching datum, so we cannot confirm the
+ * indexes match.  For the NULL partition, this is just so cheap, there's no
+ * sense in caching.
+ *
+ * Return value is index of the partition (>= 0 and < partdesc->nparts) if one
+ * found or -1 if none found.
+ */
+static int
+get_partition_for_tuple(PartitionDispatch pd, Datum *values, bool *isnull)
+{
+	int			bound_offset = -1;
+	int			part_index = -1;
+	PartitionKey key = pd->key;
+	PartitionDesc partdesc = pd->partdesc;
+	PartitionBoundInfo boundinfo = partdesc->boundinfo;
+
+	/*
+	 * In the switch statement below, when we perform a cached lookup for
+	 * RANGE and LIST partitioned tables, if we find that the last found
+	 * partition matches the 'values', we return the partition index right
+	 * away.  We do this instead of breaking out of the switch as we don't
+	 * want to execute the code about the DEFAULT partition or do any updates
+	 * for any of the cache-related fields.  That would be a waste of effort
+	 * as we already know it's not the DEFAULT partition and have no need to
+	 * increment the number of times we found the same partition any higher
+	 * than PARTITION_CACHED_FIND_THRESHOLD.
+	 */
+
+	/* Route as appropriate based on partitioning strategy. */
+	switch (key->strategy)
+	{
+		case PARTITION_STRATEGY_HASH:
+			{
+				uint64		rowHash;
+
+				/* hash partitioning is too cheap to bother caching */
+				rowHash = compute_partition_hash_value(key->partnatts,
+													   key->partsupfunc,
+													   key->partcollation,
+													   values, isnull);
+
+				/*
+				 * HASH partitions can't have a DEFAULT partition and we don't
+				 * do any caching work for them, so just return the part index
+				 */
+				return boundinfo->indexes[rowHash % boundinfo->nindexes];
+			}
+
+		case PARTITION_STRATEGY_LIST:
+			if (isnull[0])
+			{
+				/* this is far too cheap to bother doing any caching */
+				if (partition_bound_accepts_nulls(boundinfo))
+				{
+					/*
+					 * When there is a NULL partition we just return that
+					 * directly.  We don't have a bound_offset so it's not
+					 * valid to drop into the code after the switch which
+					 * checks and updates the cache fields.  We perhaps should
+					 * be invalidating the details of the last cached
+					 * partition but there's no real need to.  Keeping those
+					 * fields set gives a chance at matching to the cached
+					 * partition on the next lookup.
+					 */
+					return boundinfo->null_index;
+				}
+			}
+			else
+			{
+				bool		equal;
+
+				if (partdesc->last_found_count >= PARTITION_CACHED_FIND_THRESHOLD)
+				{
+					int			last_datum_offset = partdesc->last_found_datum_index;
+					Datum		lastDatum = boundinfo->datums[last_datum_offset][0];
+					int32		cmpval;
+
+					/* does the last found datum index match this datum? */
+					cmpval = DatumGetInt32(FunctionCall2Coll(&key->partsupfunc[0],
+															 key->partcollation[0],
+															 lastDatum,
+															 values[0]));
+
+					if (cmpval == 0)
+						return boundinfo->indexes[last_datum_offset];
+
+					/* fall-through and do a manual lookup */
+				}
+
+				bound_offset = partition_list_bsearch(key->partsupfunc,
+													  key->partcollation,
+													  boundinfo,
+													  values[0], &equal);
+				if (bound_offset >= 0 && equal)
+					part_index = boundinfo->indexes[bound_offset];
+			}
+			break;
+
+		case PARTITION_STRATEGY_RANGE:
+			{
+				bool		equal = false,
+							range_partkey_has_null = false;
+				int			i;
+
+				/*
+				 * No range includes NULL, so this will be accepted by the
+				 * default partition if there is one, and otherwise rejected.
+				 */
+				for (i = 0; i < key->partnatts; i++)
+				{
+					if (isnull[i])
+					{
+						range_partkey_has_null = true;
+						break;
+					}
+				}
+
+				/* NULLs belong in the DEFAULT partition */
+				if (range_partkey_has_null)
+					break;
+
+				if (partdesc->last_found_count >= PARTITION_CACHED_FIND_THRESHOLD)
+				{
+					int			last_datum_offset = partdesc->last_found_datum_index;
+					Datum	   *lastDatums = boundinfo->datums[last_datum_offset];
+					PartitionRangeDatumKind *kind = boundinfo->kind[last_datum_offset];
+					int32		cmpval;
+
+					/* check if the value is >= to the lower bound */
+					cmpval = partition_rbound_datum_cmp(key->partsupfunc,
+														key->partcollation,
+														lastDatums,
+														kind,
+														values,
+														key->partnatts);
+
+					/*
+					 * If it's equal to the lower bound then no need to check
+					 * the upper bound.
+					 */
+					if (cmpval == 0)
+						return boundinfo->indexes[last_datum_offset + 1];
+
+					if (cmpval < 0 && last_datum_offset + 1 < boundinfo->ndatums)
+					{
+						/* check if the value is below the upper bound */
+						lastDatums = boundinfo->datums[last_datum_offset + 1];
+						kind = boundinfo->kind[last_datum_offset + 1];
+						cmpval = partition_rbound_datum_cmp(key->partsupfunc,
+															key->partcollation,
+															lastDatums,
+															kind,
+															values,
+															key->partnatts);
+
+						if (cmpval > 0)
+							return boundinfo->indexes[last_datum_offset + 1];
+					}
+					/* fall-through and do a manual lookup */
+				}
+
+				bound_offset = partition_range_datum_bsearch(key->partsupfunc,
+															 key->partcollation,
+															 boundinfo,
+															 key->partnatts,
+															 values,
+															 &equal);
+
+				/*
+				 * The bound at bound_offset is less than or equal to the
+				 * tuple value, so the bound at offset+1 is the upper bound of
+				 * the partition we're looking for, if there actually exists
+				 * one.
+				 */
+				part_index = boundinfo->indexes[bound_offset + 1];
+			}
+			break;
+
+		default:
+			elog(ERROR, "unexpected partition strategy: %d",
+				 (int) key->strategy);
+	}
+
+	/*
+	 * part_index < 0 means we failed to find a partition of this parent. Use
+	 * the default partition, if there is one.
+	 */
+	if (part_index < 0)
+	{
+		/*
+		 * No need to reset the cache fields here.  The next set of values
+		 * might end up belonging to the cached partition, so leaving the
+		 * cache alone improves the chances of a cache hit on the next lookup.
+		 */
+		return boundinfo->default_index;
+	}
+
+	/* we should only make it here when the code above set bound_offset */
+	Assert(bound_offset >= 0);
+
+	/*
+	 * Attend to the cache fields.  If the bound_offset matches the last
+	 * cached bound offset then we've found the same partition as last time,
+	 * so bump the count by one.  If all goes well, we'll eventually reach
+	 * PARTITION_CACHED_FIND_THRESHOLD and try the cache path next time
+	 * around.  Otherwise, we'll reset the cache count back to 1 to mark that
+	 * we've found this partition for the first time.
+	 */
+	if (bound_offset == partdesc->last_found_datum_index)
+		partdesc->last_found_count++;
+	else
+	{
+		partdesc->last_found_count = 1;
+		partdesc->last_found_part_index = part_index;
+		partdesc->last_found_datum_index = bound_offset;
+	}
+
+	return part_index;
+}
+
+/*
+ * ExecBuildSlotPartitionKeyDescription
+ *
+ * This works very much like BuildIndexValueDescription() and is currently
+ * used for building error messages when ExecFindPartition() fails to find
+ * partition for a row.
+ */
+static char *
+ExecBuildSlotPartitionKeyDescription(Relation rel,
+									 Datum *values,
+									 bool *isnull,
+									 int maxfieldlen)
+{
+	StringInfoData buf;
+	PartitionKey key = RelationGetPartitionKey(rel);
+	int			partnatts = get_partition_natts(key);
+	int			i;
+	Oid			relid = RelationGetRelid(rel);
+	AclResult	aclresult;
+
+	if (check_enable_rls(relid, InvalidOid, true) == RLS_ENABLED)
+		return NULL;
+
+	/* If the user has table-level access, just go build the description. */
+	aclresult = pg_class_aclcheck(relid, GetUserId(), ACL_SELECT);
+	if (aclresult != ACLCHECK_OK)
+	{
+		/*
+		 * Step through the columns of the partition key and make sure the
+		 * user has SELECT rights on all of them.
+		 */
+		for (i = 0; i < partnatts; i++)
+		{
+			AttrNumber	attnum = get_partition_col_attnum(key, i);
+
+			/*
+			 * If this partition key column is an expression, we return no
+			 * detail rather than try to figure out what column(s) the
+			 * expression includes and if the user has SELECT rights on them.
+			 */
+			if (attnum == InvalidAttrNumber ||
+				pg_attribute_aclcheck(relid, attnum, GetUserId(),
+									  ACL_SELECT) != ACLCHECK_OK)
+				return NULL;
+		}
+	}
+
+	initStringInfo(&buf);
+	appendStringInfo(&buf, "(%s) = (",
+					 pg_get_partkeydef_columns(relid, true));
+
+	for (i = 0; i < partnatts; i++)
+	{
+		char	   *val;
+		int			vallen;
+
+		if (isnull[i])
+			val = "null";
+		else
+		{
+			Oid			foutoid;
+			bool		typisvarlena;
+
+			getTypeOutputInfo(get_partition_col_typid(key, i),
+							  &foutoid, &typisvarlena);
+			val = OidOutputFunctionCall(foutoid, values[i]);
+		}
+
+		if (i > 0)
+			appendStringInfoString(&buf, ", ");
+
+		/* truncate if needed */
+		vallen = strlen(val);
+		if (vallen <= maxfieldlen)
+			appendBinaryStringInfo(&buf, val, vallen);
+		else
+		{
+			vallen = pg_mbcliplen(val, vallen, maxfieldlen);
+			appendBinaryStringInfo(&buf, val, vallen);
+			appendStringInfoString(&buf, "...");
+		}
+	}
+
+	appendStringInfoChar(&buf, ')');
+
+	return buf.data;
+}
+
+/*
+ * adjust_partition_colnos
+ *		Adjust the list of UPDATE target column numbers to account for
+ *		attribute differences between the parent and the partition.
+ *
+ * Note: mustn't be called if no adjustment is required.
+ */
+static List *
+adjust_partition_colnos(List *colnos, ResultRelInfo *leaf_part_rri)
+{
+	TupleConversionMap *map = ExecGetChildToRootMap(leaf_part_rri);
+
+	Assert(map != NULL);
+
+	return adjust_partition_colnos_using_map(colnos, map->attrMap);
+}
+
+/*
+ * adjust_partition_colnos_using_map
+ *		Like adjust_partition_colnos, but uses a caller-supplied map instead
+ *		of assuming to map from the "root" result relation.
+ *
+ * Note: mustn't be called if no adjustment is required.
+ */
+static List *
+adjust_partition_colnos_using_map(List *colnos, AttrMap *attrMap)
+{
+	List	   *new_colnos = NIL;
+	ListCell   *lc;
+
+	Assert(attrMap != NULL);	/* else we shouldn't be here */
+
+	foreach(lc, colnos)
+	{
+		AttrNumber	parentattrno = lfirst_int(lc);
+
+		if (parentattrno <= 0 ||
+			parentattrno > attrMap->maplen ||
+			attrMap->attnums[parentattrno - 1] == 0)
+			elog(ERROR, "unexpected attno %d in target column list",
+				 parentattrno);
+		new_colnos = lappend_int(new_colnos,
+								 attrMap->attnums[parentattrno - 1]);
+	}
+
+	return new_colnos;
+}
+
+/*-------------------------------------------------------------------------
+ * Run-Time Partition Pruning Support.
+ *
+ * The following series of functions exist to support the removal of unneeded
+ * subplans for queries against partitioned tables.  The supporting functions
+ * here are designed to work with any plan type which supports an arbitrary
+ * number of subplans, e.g. Append, MergeAppend.
+ *
+ * When pruning involves comparison of a partition key to a constant, it's
+ * done by the planner.  However, if we have a comparison to a non-constant
+ * but not volatile expression, that presents an opportunity for run-time
+ * pruning by the executor, allowing irrelevant partitions to be skipped
+ * dynamically.
+ *
+ * We must distinguish expressions containing PARAM_EXEC Params from
+ * expressions that don't contain those.  Even though a PARAM_EXEC Param is
+ * considered to be a stable expression, it can change value from one plan
+ * node scan to the next during query execution.  Stable comparison
+ * expressions that don't involve such Params allow partition pruning to be
+ * done once during executor startup.  Expressions that do involve such Params
+ * require us to prune separately for each scan of the parent plan node.
+ *
+ * Note that pruning away unneeded subplans during executor startup has the
+ * added benefit of not having to initialize the unneeded subplans at all.
+ *
+ *
+ * Functions:
+ *
+ * ExecInitPartitionPruning:
+ *		Creates the PartitionPruneState required by ExecFindMatchingSubPlans.
+ *		Details stored include how to map the partition index returned by the
+ *		partition pruning code into subplan indexes.  Also determines the set
+ *		of subplans to initialize considering the result of performing initial
+ *		pruning steps if any.  Maps in PartitionPruneState are updated to
+ *		account for initial pruning possibly having eliminated some of the
+ *		subplans.
+ *
+ * ExecFindMatchingSubPlans:
+ *		Returns indexes of matching subplans after evaluating the expressions
+ *		that are safe to evaluate at a given point.  This function is first
+ *		called during ExecInitPartitionPruning() to find the initially
+ *		matching subplans based on performing the initial pruning steps and
+ *		then must be called again each time the value of a Param listed in
+ *		PartitionPruneState's 'execparamids' changes.
+ *-------------------------------------------------------------------------
+ */
+
+/*
+ * ExecInitPartitionPruning
+ *		Initialize data structure needed for run-time partition pruning and
+ *		do initial pruning if needed
+ *
+ * On return, *initially_valid_subplans is assigned the set of indexes of
+ * child subplans that must be initialized along with the parent plan node.
+ * Initial pruning is performed here if needed and in that case only the
+ * surviving subplans' indexes are added.
+ *
+ * If subplans are indeed pruned, subplan_map arrays contained in the returned
+ * PartitionPruneState are re-sequenced to not count those, though only if the
+ * maps will be needed for subsequent execution pruning passes.
+ */
+PartitionPruneState *
+ExecInitPartitionPruning(PlanState *planstate,
+						 int n_total_subplans,
+						 PartitionPruneInfo *pruneinfo,
+						 Bitmapset **initially_valid_subplans)
+{
+	PartitionPruneState *prunestate;
+	EState	   *estate = planstate->state;
+
+	/* We may need an expression context to evaluate partition exprs */
+	ExecAssignExprContext(estate, planstate);
+
+	/* Create the working data structure for pruning */
+	prunestate = CreatePartitionPruneState(planstate, pruneinfo);
+
+	/*
+	 * Perform an initial partition prune pass, if required.
+	 */
+	if (prunestate->do_initial_prune)
+		*initially_valid_subplans = ExecFindMatchingSubPlans(prunestate, true);
+	else
+	{
+		/* No pruning, so we'll need to initialize all subplans */
+		Assert(n_total_subplans > 0);
+		*initially_valid_subplans = bms_add_range(NULL, 0,
+												  n_total_subplans - 1);
+	}
+
+	/*
+	 * Re-sequence subplan indexes contained in prunestate to account for any
+	 * that were removed above due to initial pruning.  No need to do this if
+	 * no steps were removed.
+	 */
+	if (bms_num_members(*initially_valid_subplans) < n_total_subplans)
+	{
+		/*
+		 * We can safely skip this when !do_exec_prune, even though that
+		 * leaves invalid data in prunestate, because that data won't be
+		 * consulted again (cf initial Assert in ExecFindMatchingSubPlans).
+		 */
+		if (prunestate->do_exec_prune)
+			PartitionPruneFixSubPlanMap(prunestate,
+										*initially_valid_subplans,
+										n_total_subplans);
+	}
+
+	return prunestate;
+}
+
+/*
+ * CreatePartitionPruneState
+ *		Build the data structure required for calling ExecFindMatchingSubPlans
+ *
+ * 'planstate' is the parent plan node's execution state.
+ *
+ * 'pruneinfo' is a PartitionPruneInfo as generated by
+ * make_partition_pruneinfo.  Here we build a PartitionPruneState containing a
+ * PartitionPruningData for each partitioning hierarchy (i.e., each sublist of
+ * pruneinfo->prune_infos), each of which contains a PartitionedRelPruningData
+ * for each PartitionedRelPruneInfo appearing in that sublist.  This two-level
+ * system is needed to keep from confusing the different hierarchies when a
+ * UNION ALL contains multiple partitioned tables as children.  The data
+ * stored in each PartitionedRelPruningData can be re-used each time we
+ * re-evaluate which partitions match the pruning steps provided in each
+ * PartitionedRelPruneInfo.
+ */
+static PartitionPruneState *
+CreatePartitionPruneState(PlanState *planstate, PartitionPruneInfo *pruneinfo)
+{
+	EState	   *estate = planstate->state;
+	PartitionPruneState *prunestate;
+	int			n_part_hierarchies;
+	ListCell   *lc;
+	int			i;
+	ExprContext *econtext = planstate->ps_ExprContext;
+
+	/* For data reading, executor always omits detached partitions */
+	if (estate->es_partition_directory == NULL)
+		estate->es_partition_directory =
+			CreatePartitionDirectory(estate->es_query_cxt, false);
+
+	n_part_hierarchies = list_length(pruneinfo->prune_infos);
+	Assert(n_part_hierarchies > 0);
+
+	/*
+	 * Allocate the data structure
+	 */
+	prunestate = (PartitionPruneState *)
+		palloc(offsetof(PartitionPruneState, partprunedata) +
+			   sizeof(PartitionPruningData *) * n_part_hierarchies);
+
+	prunestate->execparamids = NULL;
+	/* other_subplans can change at runtime, so we need our own copy */
+	prunestate->other_subplans = bms_copy(pruneinfo->other_subplans);
+	prunestate->do_initial_prune = false;	/* may be set below */
+	prunestate->do_exec_prune = false;	/* may be set below */
+	prunestate->num_partprunedata = n_part_hierarchies;
+
+	/*
+	 * Create a short-term memory context which we'll use when making calls to
+	 * the partition pruning functions.  This avoids possible memory leaks,
+	 * since the pruning functions call comparison functions that aren't under
+	 * our control.
+	 */
+	prunestate->prune_context =
+		AllocSetContextCreate(CurrentMemoryContext,
+							  "Partition Prune",
+							  ALLOCSET_DEFAULT_SIZES);
+
+	i = 0;
+	foreach(lc, pruneinfo->prune_infos)
+	{
+		List	   *partrelpruneinfos = lfirst_node(List, lc);
+		int			npartrelpruneinfos = list_length(partrelpruneinfos);
+		PartitionPruningData *prunedata;
+		ListCell   *lc2;
+		int			j;
+
+		prunedata = (PartitionPruningData *)
+			palloc(offsetof(PartitionPruningData, partrelprunedata) +
+				   npartrelpruneinfos * sizeof(PartitionedRelPruningData));
+		prunestate->partprunedata[i] = prunedata;
+		prunedata->num_partrelprunedata = npartrelpruneinfos;
+
+		j = 0;
+		foreach(lc2, partrelpruneinfos)
+		{
+			PartitionedRelPruneInfo *pinfo = lfirst_node(PartitionedRelPruneInfo, lc2);
+			PartitionedRelPruningData *pprune = &prunedata->partrelprunedata[j];
+			Relation	partrel;
+			PartitionDesc partdesc;
+			PartitionKey partkey;
+
+			/*
+			 * We can rely on the copies of the partitioned table's partition
+			 * key and partition descriptor appearing in its relcache entry,
+			 * because that entry will be held open and locked for the
+			 * duration of this executor run.
+			 */
+			partrel = ExecGetRangeTableRelation(estate, pinfo->rtindex);
+			partkey = RelationGetPartitionKey(partrel);
+			partdesc = PartitionDirectoryLookup(estate->es_partition_directory,
+												partrel);
+
+			/*
+			 * Initialize the subplan_map and subpart_map.
+			 *
+			 * Because we request detached partitions to be included, and
+			 * detaching waits for old transactions, it is safe to assume that
+			 * no partitions have disappeared since this query was planned.
+			 *
+			 * However, new partitions may have been added.
+			 */
+			Assert(partdesc->nparts >= pinfo->nparts);
+			pprune->nparts = partdesc->nparts;
+			pprune->subplan_map = palloc(sizeof(int) * partdesc->nparts);
+			if (partdesc->nparts == pinfo->nparts)
+			{
+				/*
+				 * There are no new partitions, so this is simple.  We can
+				 * simply point to the subpart_map from the plan, but we must
+				 * copy the subplan_map since we may change it later.
+				 */
+				pprune->subpart_map = pinfo->subpart_map;
+				memcpy(pprune->subplan_map, pinfo->subplan_map,
+					   sizeof(int) * pinfo->nparts);
+
+				/*
+				 * Double-check that the list of unpruned relations has not
+				 * changed.  (Pruned partitions are not in relid_map[].)
+				 */
+#ifdef USE_ASSERT_CHECKING
+				for (int k = 0; k < pinfo->nparts; k++)
+				{
+					Assert(partdesc->oids[k] == pinfo->relid_map[k] ||
+						   pinfo->subplan_map[k] == -1);
+				}
+#endif
+			}
+			else
+			{
+				int			pd_idx = 0;
+				int			pp_idx;
+
+				/*
+				 * Some new partitions have appeared since plan time, and
+				 * those are reflected in our PartitionDesc but were not
+				 * present in the one used to construct subplan_map and
+				 * subpart_map.  So we must construct new and longer arrays
+				 * where the partitions that were originally present map to
+				 * the same sub-structures, and any added partitions map to
+				 * -1, as if the new partitions had been pruned.
+				 *
+				 * Note: pinfo->relid_map[] may contain InvalidOid entries for
+				 * partitions pruned by the planner.  We cannot tell exactly
+				 * which of the partdesc entries these correspond to, but we
+				 * don't have to; just skip over them.  The non-pruned
+				 * relid_map entries, however, had better be a subset of the
+				 * partdesc entries and in the same order.
+				 */
+				pprune->subpart_map = palloc(sizeof(int) * partdesc->nparts);
+				for (pp_idx = 0; pp_idx < partdesc->nparts; pp_idx++)
+				{
+					/* Skip any InvalidOid relid_map entries */
+					while (pd_idx < pinfo->nparts &&
+						   !OidIsValid(pinfo->relid_map[pd_idx]))
+						pd_idx++;
+
+					if (pd_idx < pinfo->nparts &&
+						pinfo->relid_map[pd_idx] == partdesc->oids[pp_idx])
+					{
+						/* match... */
+						pprune->subplan_map[pp_idx] =
+							pinfo->subplan_map[pd_idx];
+						pprune->subpart_map[pp_idx] =
+							pinfo->subpart_map[pd_idx];
+						pd_idx++;
+					}
+					else
+					{
+						/* this partdesc entry is not in the plan */
+						pprune->subplan_map[pp_idx] = -1;
+						pprune->subpart_map[pp_idx] = -1;
+					}
+				}
+
+				/*
+				 * It might seem that we need to skip any trailing InvalidOid
+				 * entries in pinfo->relid_map before checking that we scanned
+				 * all of the relid_map.  But we will have skipped them above,
+				 * because they must correspond to some partdesc->oids
+				 * entries; we just couldn't tell which.
+				 */
+				if (pd_idx != pinfo->nparts)
+					elog(ERROR, "could not match partition child tables to plan elements");
+			}
+
+			/* present_parts is also subject to later modification */
+			pprune->present_parts = bms_copy(pinfo->present_parts);
+
+			/*
+			 * Initialize pruning contexts as needed.  Note that we must skip
+			 * execution-time partition pruning in EXPLAIN (GENERIC_PLAN),
+			 * since parameter values may be missing.
+			 */
+			pprune->initial_pruning_steps = pinfo->initial_pruning_steps;
+			if (pinfo->initial_pruning_steps &&
+				!(econtext->ecxt_estate->es_top_eflags & EXEC_FLAG_EXPLAIN_GENERIC))
+			{
+				InitPartitionPruneContext(&pprune->initial_context,
+										  pinfo->initial_pruning_steps,
+										  partdesc, partkey, planstate,
+										  econtext);
+				/* Record whether initial pruning is needed at any level */
+				prunestate->do_initial_prune = true;
+			}
+			pprune->exec_pruning_steps = pinfo->exec_pruning_steps;
+			if (pinfo->exec_pruning_steps &&
+				!(econtext->ecxt_estate->es_top_eflags & EXEC_FLAG_EXPLAIN_GENERIC))
+			{
+				InitPartitionPruneContext(&pprune->exec_context,
+										  pinfo->exec_pruning_steps,
+										  partdesc, partkey, planstate,
+										  econtext);
+				/* Record whether exec pruning is needed at any level */
+				prunestate->do_exec_prune = true;
+			}
+
+			/*
+			 * Accumulate the IDs of all PARAM_EXEC Params affecting the
+			 * partitioning decisions at this plan node.
+			 */
+			prunestate->execparamids = bms_add_members(prunestate->execparamids,
+													   pinfo->execparamids);
+
+			j++;
+		}
+		i++;
+	}
+
+	return prunestate;
+}
+
+/*
+ * Initialize a PartitionPruneContext for the given list of pruning steps.
+ */
+static void
+InitPartitionPruneContext(PartitionPruneContext *context,
+						  List *pruning_steps,
+						  PartitionDesc partdesc,
+						  PartitionKey partkey,
+						  PlanState *planstate,
+						  ExprContext *econtext)
+{
+	int			n_steps;
+	int			partnatts;
+	ListCell   *lc;
+
+	n_steps = list_length(pruning_steps);
+
+	context->strategy = partkey->strategy;
+	context->partnatts = partnatts = partkey->partnatts;
+	context->nparts = partdesc->nparts;
+	context->boundinfo = partdesc->boundinfo;
+	context->partcollation = partkey->partcollation;
+	context->partsupfunc = partkey->partsupfunc;
+
+	/* We'll look up type-specific support functions as needed */
+	context->stepcmpfuncs = (FmgrInfo *)
+		palloc0(sizeof(FmgrInfo) * n_steps * partnatts);
+
+	context->ppccontext = CurrentMemoryContext;
+	context->planstate = planstate;
+	context->exprcontext = econtext;
+
+	/* Initialize expression state for each expression we need */
+	context->exprstates = (ExprState **)
+		palloc0(sizeof(ExprState *) * n_steps * partnatts);
+	foreach(lc, pruning_steps)
+	{
+		PartitionPruneStepOp *step = (PartitionPruneStepOp *) lfirst(lc);
+		ListCell   *lc2 = list_head(step->exprs);
+		int			keyno;
+
+		/* not needed for other step kinds */
+		if (!IsA(step, PartitionPruneStepOp))
+			continue;
+
+		Assert(list_length(step->exprs) <= partnatts);
+
+		for (keyno = 0; keyno < partnatts; keyno++)
+		{
+			if (bms_is_member(keyno, step->nullkeys))
+				continue;
+
+			if (lc2 != NULL)
+			{
+				Expr	   *expr = lfirst(lc2);
+
+				/* not needed for Consts */
+				if (!IsA(expr, Const))
+				{
+					int			stateidx = PruneCxtStateIdx(partnatts,
+															step->step.step_id,
+															keyno);
+
+					/*
+					 * When planstate is NULL, pruning_steps is known not to
+					 * contain any expressions that depend on the parent plan.
+					 * Information of any available EXTERN parameters must be
+					 * passed explicitly in that case, which the caller must
+					 * have made available via econtext.
+					 */
+					if (planstate == NULL)
+						context->exprstates[stateidx] =
+							ExecInitExprWithParams(expr,
+												   econtext->ecxt_param_list_info);
+					else
+						context->exprstates[stateidx] =
+							ExecInitExpr(expr, context->planstate);
+				}
+				lc2 = lnext(step->exprs, lc2);
+			}
+		}
+	}
+}
+
+/*
+ * PartitionPruneFixSubPlanMap
+ *		Fix mapping of partition indexes to subplan indexes contained in
+ *		prunestate by considering the new list of subplans that survived
+ *		initial pruning
+ *
+ * Current values of the indexes present in PartitionPruneState count all the
+ * subplans that would be present before initial pruning was done.  If initial
+ * pruning got rid of some of the subplans, any subsequent pruning passes will
+ * be looking at a different set of target subplans to choose from than those
+ * in the pre-initial-pruning set, so the maps in PartitionPruneState
+ * containing those indexes must be updated to reflect the new indexes of
+ * subplans in the post-initial-pruning set.
+ */
+static void
+PartitionPruneFixSubPlanMap(PartitionPruneState *prunestate,
+							Bitmapset *initially_valid_subplans,
+							int n_total_subplans)
+{
+	int		   *new_subplan_indexes;
+	Bitmapset  *new_other_subplans;
+	int			i;
+	int			newidx;
+
+	/*
+	 * First we must build a temporary array which maps old subplan indexes to
+	 * new ones.  For convenience of initialization, we use 1-based indexes in
+	 * this array and leave pruned items as 0.
+	 */
+	new_subplan_indexes = (int *) palloc0(sizeof(int) * n_total_subplans);
+	newidx = 1;
+	i = -1;
+	while ((i = bms_next_member(initially_valid_subplans, i)) >= 0)
+	{
+		Assert(i < n_total_subplans);
+		new_subplan_indexes[i] = newidx++;
+	}
+
+	/*
+	 * Now we can update each PartitionedRelPruneInfo's subplan_map with new
+	 * subplan indexes.  We must also recompute its present_parts bitmap.
+	 */
+	for (i = 0; i < prunestate->num_partprunedata; i++)
+	{
+		PartitionPruningData *prunedata = prunestate->partprunedata[i];
+		int			j;
+
+		/*
+		 * Within each hierarchy, we perform this loop in back-to-front order
+		 * so that we determine present_parts for the lowest-level partitioned
+		 * tables first.  This way we can tell whether a sub-partitioned
+		 * table's partitions were entirely pruned so we can exclude it from
+		 * the current level's present_parts.
+		 */
+		for (j = prunedata->num_partrelprunedata - 1; j >= 0; j--)
+		{
+			PartitionedRelPruningData *pprune = &prunedata->partrelprunedata[j];
+			int			nparts = pprune->nparts;
+			int			k;
+
+			/* We just rebuild present_parts from scratch */
+			bms_free(pprune->present_parts);
+			pprune->present_parts = NULL;
+
+			for (k = 0; k < nparts; k++)
+			{
+				int			oldidx = pprune->subplan_map[k];
+				int			subidx;
+
+				/*
+				 * If this partition existed as a subplan then change the old
+				 * subplan index to the new subplan index.  The new index may
+				 * become -1 if the partition was pruned above, or it may just
+				 * come earlier in the subplan list due to some subplans being
+				 * removed earlier in the list.  If it's a subpartition, add
+				 * it to present_parts unless it's entirely pruned.
+				 */
+				if (oldidx >= 0)
+				{
+					Assert(oldidx < n_total_subplans);
+					pprune->subplan_map[k] = new_subplan_indexes[oldidx] - 1;
+
+					if (new_subplan_indexes[oldidx] > 0)
+						pprune->present_parts =
+							bms_add_member(pprune->present_parts, k);
+				}
+				else if ((subidx = pprune->subpart_map[k]) >= 0)
+				{
+					PartitionedRelPruningData *subprune;
+
+					subprune = &prunedata->partrelprunedata[subidx];
+
+					if (!bms_is_empty(subprune->present_parts))
+						pprune->present_parts =
+							bms_add_member(pprune->present_parts, k);
+				}
+			}
+		}
+	}
+
+	/*
+	 * We must also recompute the other_subplans set, since indexes in it may
+	 * change.
+	 */
+	new_other_subplans = NULL;
+	i = -1;
+	while ((i = bms_next_member(prunestate->other_subplans, i)) >= 0)
+		new_other_subplans = bms_add_member(new_other_subplans,
+											new_subplan_indexes[i] - 1);
+
+	bms_free(prunestate->other_subplans);
+	prunestate->other_subplans = new_other_subplans;
+
+	pfree(new_subplan_indexes);
+}
+
+/*
+ * ExecFindMatchingSubPlans
+ *		Determine which subplans match the pruning steps detailed in
+ *		'prunestate' for the current comparison expression values.
+ *
+ * Pass initial_prune if PARAM_EXEC Params cannot yet be evaluated.  This
+ * differentiates the initial executor-time pruning step from later
+ * runtime pruning.
+ */
+Bitmapset *
+ExecFindMatchingSubPlans(PartitionPruneState *prunestate,
+						 bool initial_prune)
+{
+	Bitmapset  *result = NULL;
+	MemoryContext oldcontext;
+	int			i;
+
+	/*
+	 * Either we're here on the initial prune done during pruning
+	 * initialization, or we're at a point where PARAM_EXEC Params can be
+	 * evaluated *and* there are steps in which to do so.
+	 */
+	Assert(initial_prune || prunestate->do_exec_prune);
+
+	/*
+	 * Switch to a temp context to avoid leaking memory in the executor's
+	 * query-lifespan memory context.
+	 */
+	oldcontext = MemoryContextSwitchTo(prunestate->prune_context);
+
+	/*
+	 * For each hierarchy, do the pruning tests, and add nondeletable
+	 * subplans' indexes to "result".
+	 */
+	for (i = 0; i < prunestate->num_partprunedata; i++)
+	{
+		PartitionPruningData *prunedata = prunestate->partprunedata[i];
+		PartitionedRelPruningData *pprune;
+
+		/*
+		 * We pass the zeroth item, belonging to the root table of the
+		 * hierarchy, and find_matching_subplans_recurse() takes care of
+		 * recursing to other (lower-level) parents as needed.
+		 */
+		pprune = &prunedata->partrelprunedata[0];
+		find_matching_subplans_recurse(prunedata, pprune, initial_prune,
+									   &result);
+
+		/* Expression eval may have used space in ExprContext too */
+		if (pprune->exec_pruning_steps)
+			ResetExprContext(pprune->exec_context.exprcontext);
+	}
+
+	/* Add in any subplans that partition pruning didn't account for */
+	result = bms_add_members(result, prunestate->other_subplans);
+
+	MemoryContextSwitchTo(oldcontext);
+
+	/* Copy result out of the temp context before we reset it */
+	result = bms_copy(result);
+
+	MemoryContextReset(prunestate->prune_context);
+
+	return result;
+}
+
+/*
+ * find_matching_subplans_recurse
+ *		Recursive worker function for ExecFindMatchingSubPlans
+ *
+ * Adds valid (non-prunable) subplan IDs to *validsubplans
+ */
+static void
+find_matching_subplans_recurse(PartitionPruningData *prunedata,
+							   PartitionedRelPruningData *pprune,
+							   bool initial_prune,
+							   Bitmapset **validsubplans)
+{
+	Bitmapset  *partset;
+	int			i;
+
+	/* Guard against stack overflow due to overly deep partition hierarchy. */
+	check_stack_depth();
+
+	/*
+	 * Prune as appropriate, if we have pruning steps matching the current
+	 * execution context.  Otherwise just include all partitions at this
+	 * level.
+	 */
+	if (initial_prune && pprune->initial_pruning_steps)
+		partset = get_matching_partitions(&pprune->initial_context,
+										  pprune->initial_pruning_steps);
+	else if (!initial_prune && pprune->exec_pruning_steps)
+		partset = get_matching_partitions(&pprune->exec_context,
+										  pprune->exec_pruning_steps);
+	else
+		partset = pprune->present_parts;
+
+	/* Translate partset into subplan indexes */
+	i = -1;
+	while ((i = bms_next_member(partset, i)) >= 0)
+	{
+		if (pprune->subplan_map[i] >= 0)
+			*validsubplans = bms_add_member(*validsubplans,
+											pprune->subplan_map[i]);
+		else
+		{
+			int			partidx = pprune->subpart_map[i];
+
+			if (partidx >= 0)
+				find_matching_subplans_recurse(prunedata,
+											   &prunedata->partrelprunedata[partidx],
+											   initial_prune, validsubplans);
+			else
+			{
+				/*
+				 * We get here if the planner already pruned all the sub-
+				 * partitions for this partition.  Silently ignore this
+				 * partition in this case.  The end result is the same: we
+				 * would have pruned all partitions just the same, but we
+				 * don't have any pruning steps to execute to verify this.
+				 */
+			}
+		}
+	}
+}