Adding upstream version 15.5.upstream/15.5

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

1 files changed, 4473 insertions, 0 deletions

diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
new file mode 100644
index 0000000..7f822ef
--- /dev/null
+++ b/src/backend/executor/nodeModifyTable.c
@@ -0,0 +1,4473 @@
+/*-------------------------------------------------------------------------
+ *
+ * nodeModifyTable.c
+ *	  routines to handle ModifyTable nodes.
+ *
+ * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  src/backend/executor/nodeModifyTable.c
+ *
+ *-------------------------------------------------------------------------
+ */
+/* INTERFACE ROUTINES
+ *		ExecInitModifyTable - initialize the ModifyTable node
+ *		ExecModifyTable		- retrieve the next tuple from the node
+ *		ExecEndModifyTable	- shut down the ModifyTable node
+ *		ExecReScanModifyTable - rescan the ModifyTable node
+ *
+ *	 NOTES
+ *		The ModifyTable node receives input from its outerPlan, which is
+ *		the data to insert for INSERT cases, the changed columns' new
+ *		values plus row-locating info for UPDATE and MERGE cases, or just the
+ *		row-locating info for DELETE cases.
+ *
+ *		MERGE runs a join between the source relation and the target
+ *		table; if any WHEN NOT MATCHED clauses are present, then the
+ *		join is an outer join.  In this case, any unmatched tuples will
+ *		have NULL row-locating info, and only INSERT can be run. But for
+ *		matched tuples, then row-locating info is used to determine the
+ *		tuple to UPDATE or DELETE. When all clauses are WHEN MATCHED,
+ *		then an inner join is used, so all tuples contain row-locating info.
+ *
+ *		If the query specifies RETURNING, then the ModifyTable returns a
+ *		RETURNING tuple after completing each row insert, update, or delete.
+ *		It must be called again to continue the operation.  Without RETURNING,
+ *		we just loop within the node until all the work is done, then
+ *		return NULL.  This avoids useless call/return overhead.  (MERGE does
+ *		not support RETURNING.)
+ */
+
+#include "postgres.h"
+
+#include "access/heapam.h"
+#include "access/htup_details.h"
+#include "access/tableam.h"
+#include "access/xact.h"
+#include "catalog/catalog.h"
+#include "commands/trigger.h"
+#include "executor/execPartition.h"
+#include "executor/executor.h"
+#include "executor/nodeModifyTable.h"
+#include "foreign/fdwapi.h"
+#include "miscadmin.h"
+#include "nodes/nodeFuncs.h"
+#include "optimizer/optimizer.h"
+#include "rewrite/rewriteHandler.h"
+#include "storage/bufmgr.h"
+#include "storage/lmgr.h"
+#include "utils/builtins.h"
+#include "utils/datum.h"
+#include "utils/memutils.h"
+#include "utils/rel.h"
+
+
+typedef struct MTTargetRelLookup
+{
+	Oid			relationOid;	/* hash key, must be first */
+	int			relationIndex;	/* rel's index in resultRelInfo[] array */
+} MTTargetRelLookup;
+
+/*
+ * Context struct for a ModifyTable operation, containing basic execution
+ * state and some output variables populated by ExecUpdateAct() and
+ * ExecDeleteAct() to report the result of their actions to callers.
+ */
+typedef struct ModifyTableContext
+{
+	/* Operation state */
+	ModifyTableState *mtstate;
+	EPQState   *epqstate;
+	EState	   *estate;
+
+	/*
+	 * Slot containing tuple obtained from ModifyTable's subplan.  Used to
+	 * access "junk" columns that are not going to be stored.
+	 */
+	TupleTableSlot *planSlot;
+
+	/* MERGE specific */
+	MergeActionState *relaction;	/* MERGE action in progress */
+
+	/*
+	 * Information about the changes that were made concurrently to a tuple
+	 * being updated or deleted
+	 */
+	TM_FailureData tmfd;
+
+	/*
+	 * The tuple projected by the INSERT's RETURNING clause, when doing a
+	 * cross-partition UPDATE
+	 */
+	TupleTableSlot *cpUpdateReturningSlot;
+} ModifyTableContext;
+
+/*
+ * Context struct containing output data specific to UPDATE operations.
+ */
+typedef struct UpdateContext
+{
+	bool		updated;		/* did UPDATE actually occur? */
+	bool		updateIndexes;	/* index update required? */
+	bool		crossPartUpdate;	/* was it a cross-partition update? */
+
+	/*
+	 * Lock mode to acquire on the latest tuple version before performing
+	 * EvalPlanQual on it
+	 */
+	LockTupleMode lockmode;
+} UpdateContext;
+
+
+static void ExecBatchInsert(ModifyTableState *mtstate,
+							ResultRelInfo *resultRelInfo,
+							TupleTableSlot **slots,
+							TupleTableSlot **planSlots,
+							int numSlots,
+							EState *estate,
+							bool canSetTag);
+static void ExecPendingInserts(EState *estate);
+static void ExecCrossPartitionUpdateForeignKey(ModifyTableContext *context,
+											   ResultRelInfo *sourcePartInfo,
+											   ResultRelInfo *destPartInfo,
+											   ItemPointer tupleid,
+											   TupleTableSlot *oldslot,
+											   TupleTableSlot *newslot);
+static bool ExecOnConflictUpdate(ModifyTableContext *context,
+								 ResultRelInfo *resultRelInfo,
+								 ItemPointer conflictTid,
+								 TupleTableSlot *excludedSlot,
+								 bool canSetTag,
+								 TupleTableSlot **returning);
+static TupleTableSlot *ExecPrepareTupleRouting(ModifyTableState *mtstate,
+											   EState *estate,
+											   PartitionTupleRouting *proute,
+											   ResultRelInfo *targetRelInfo,
+											   TupleTableSlot *slot,
+											   ResultRelInfo **partRelInfo);
+
+static TupleTableSlot *ExecMerge(ModifyTableContext *context,
+								 ResultRelInfo *resultRelInfo,
+								 ItemPointer tupleid,
+								 bool canSetTag);
+static void ExecInitMerge(ModifyTableState *mtstate, EState *estate);
+static bool ExecMergeMatched(ModifyTableContext *context,
+							 ResultRelInfo *resultRelInfo,
+							 ItemPointer tupleid,
+							 bool canSetTag);
+static void ExecMergeNotMatched(ModifyTableContext *context,
+								ResultRelInfo *resultRelInfo,
+								bool canSetTag);
+
+
+/*
+ * Verify that the tuples to be produced by INSERT match the
+ * target relation's rowtype
+ *
+ * We do this to guard against stale plans.  If plan invalidation is
+ * functioning properly then we should never get a failure here, but better
+ * safe than sorry.  Note that this is called after we have obtained lock
+ * on the target rel, so the rowtype can't change underneath us.
+ *
+ * The plan output is represented by its targetlist, because that makes
+ * handling the dropped-column case easier.
+ *
+ * We used to use this for UPDATE as well, but now the equivalent checks
+ * are done in ExecBuildUpdateProjection.
+ */
+static void
+ExecCheckPlanOutput(Relation resultRel, List *targetList)
+{
+	TupleDesc	resultDesc = RelationGetDescr(resultRel);
+	int			attno = 0;
+	ListCell   *lc;
+
+	foreach(lc, targetList)
+	{
+		TargetEntry *tle = (TargetEntry *) lfirst(lc);
+		Form_pg_attribute attr;
+
+		Assert(!tle->resjunk);	/* caller removed junk items already */
+
+		if (attno >= resultDesc->natts)
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("table row type and query-specified row type do not match"),
+					 errdetail("Query has too many columns.")));
+		attr = TupleDescAttr(resultDesc, attno);
+		attno++;
+
+		if (!attr->attisdropped)
+		{
+			/* Normal case: demand type match */
+			if (exprType((Node *) tle->expr) != attr->atttypid)
+				ereport(ERROR,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("table row type and query-specified row type do not match"),
+						 errdetail("Table has type %s at ordinal position %d, but query expects %s.",
+								   format_type_be(attr->atttypid),
+								   attno,
+								   format_type_be(exprType((Node *) tle->expr)))));
+		}
+		else
+		{
+			/*
+			 * For a dropped column, we can't check atttypid (it's likely 0).
+			 * In any case the planner has most likely inserted an INT4 null.
+			 * What we insist on is just *some* NULL constant.
+			 */
+			if (!IsA(tle->expr, Const) ||
+				!((Const *) tle->expr)->constisnull)
+				ereport(ERROR,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("table row type and query-specified row type do not match"),
+						 errdetail("Query provides a value for a dropped column at ordinal position %d.",
+								   attno)));
+		}
+	}
+	if (attno != resultDesc->natts)
+		ereport(ERROR,
+				(errcode(ERRCODE_DATATYPE_MISMATCH),
+				 errmsg("table row type and query-specified row type do not match"),
+				 errdetail("Query has too few columns.")));
+}
+
+/*
+ * ExecProcessReturning --- evaluate a RETURNING list
+ *
+ * resultRelInfo: current result rel
+ * tupleSlot: slot holding tuple actually inserted/updated/deleted
+ * planSlot: slot holding tuple returned by top subplan node
+ *
+ * Note: If tupleSlot is NULL, the FDW should have already provided econtext's
+ * scan tuple.
+ *
+ * Returns a slot holding the result tuple
+ */
+static TupleTableSlot *
+ExecProcessReturning(ResultRelInfo *resultRelInfo,
+					 TupleTableSlot *tupleSlot,
+					 TupleTableSlot *planSlot)
+{
+	ProjectionInfo *projectReturning = resultRelInfo->ri_projectReturning;
+	ExprContext *econtext = projectReturning->pi_exprContext;
+
+	/* Make tuple and any needed join variables available to ExecProject */
+	if (tupleSlot)
+		econtext->ecxt_scantuple = tupleSlot;
+	econtext->ecxt_outertuple = planSlot;
+
+	/*
+	 * RETURNING expressions might reference the tableoid column, so
+	 * reinitialize tts_tableOid before evaluating them.
+	 */
+	econtext->ecxt_scantuple->tts_tableOid =
+		RelationGetRelid(resultRelInfo->ri_RelationDesc);
+
+	/* Compute the RETURNING expressions */
+	return ExecProject(projectReturning);
+}
+
+/*
+ * ExecCheckTupleVisible -- verify tuple is visible
+ *
+ * It would not be consistent with guarantees of the higher isolation levels to
+ * proceed with avoiding insertion (taking speculative insertion's alternative
+ * path) on the basis of another tuple that is not visible to MVCC snapshot.
+ * Check for the need to raise a serialization failure, and do so as necessary.
+ */
+static void
+ExecCheckTupleVisible(EState *estate,
+					  Relation rel,
+					  TupleTableSlot *slot)
+{
+	if (!IsolationUsesXactSnapshot())
+		return;
+
+	if (!table_tuple_satisfies_snapshot(rel, slot, estate->es_snapshot))
+	{
+		Datum		xminDatum;
+		TransactionId xmin;
+		bool		isnull;
+
+		xminDatum = slot_getsysattr(slot, MinTransactionIdAttributeNumber, &isnull);
+		Assert(!isnull);
+		xmin = DatumGetTransactionId(xminDatum);
+
+		/*
+		 * We should not raise a serialization failure if the conflict is
+		 * against a tuple inserted by our own transaction, even if it's not
+		 * visible to our snapshot.  (This would happen, for example, if
+		 * conflicting keys are proposed for insertion in a single command.)
+		 */
+		if (!TransactionIdIsCurrentTransactionId(xmin))
+			ereport(ERROR,
+					(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+					 errmsg("could not serialize access due to concurrent update")));
+	}
+}
+
+/*
+ * ExecCheckTIDVisible -- convenience variant of ExecCheckTupleVisible()
+ */
+static void
+ExecCheckTIDVisible(EState *estate,
+					ResultRelInfo *relinfo,
+					ItemPointer tid,
+					TupleTableSlot *tempSlot)
+{
+	Relation	rel = relinfo->ri_RelationDesc;
+
+	/* Redundantly check isolation level */
+	if (!IsolationUsesXactSnapshot())
+		return;
+
+	if (!table_tuple_fetch_row_version(rel, tid, SnapshotAny, tempSlot))
+		elog(ERROR, "failed to fetch conflicting tuple for ON CONFLICT");
+	ExecCheckTupleVisible(estate, rel, tempSlot);
+	ExecClearTuple(tempSlot);
+}
+
+/*
+ * Initialize to compute stored generated columns for a tuple
+ *
+ * This fills the resultRelInfo's ri_GeneratedExprs field and makes an
+ * associated ResultRelInfoExtra struct to hold ri_extraUpdatedCols.
+ * (Currently, ri_extraUpdatedCols is consulted only in UPDATE, but we
+ * must fill it in other cases too, since for example cmdtype might be
+ * MERGE yet an UPDATE might happen later.)
+ */
+void
+ExecInitStoredGenerated(ResultRelInfo *resultRelInfo,
+						EState *estate,
+						CmdType cmdtype)
+{
+	Relation	rel = resultRelInfo->ri_RelationDesc;
+	TupleDesc	tupdesc = RelationGetDescr(rel);
+	int			natts = tupdesc->natts;
+	Bitmapset  *updatedCols;
+	ResultRelInfoExtra *rextra;
+	MemoryContext oldContext;
+
+	/* Don't call twice */
+	Assert(resultRelInfo->ri_GeneratedExprs == NULL);
+
+	/* Nothing to do if no generated columns */
+	if (!(tupdesc->constr && tupdesc->constr->has_generated_stored))
+		return;
+
+	/*
+	 * In an UPDATE, we can skip computing any generated columns that do not
+	 * depend on any UPDATE target column.  But if there is a BEFORE ROW
+	 * UPDATE trigger, we cannot skip because the trigger might change more
+	 * columns.
+	 */
+	if (cmdtype == CMD_UPDATE &&
+		!(rel->trigdesc && rel->trigdesc->trig_update_before_row))
+		updatedCols = ExecGetUpdatedCols(resultRelInfo, estate);
+	else
+		updatedCols = NULL;
+
+	/*
+	 * Make sure these data structures are built in the per-query memory
+	 * context so they'll survive throughout the query.
+	 */
+	oldContext = MemoryContextSwitchTo(estate->es_query_cxt);
+
+	resultRelInfo->ri_GeneratedExprs =
+		(ExprState **) palloc0(natts * sizeof(ExprState *));
+	resultRelInfo->ri_NumGeneratedNeeded = 0;
+
+	rextra = palloc_object(ResultRelInfoExtra);
+	rextra->rinfo = resultRelInfo;
+	rextra->ri_extraUpdatedCols = NULL;
+	estate->es_resultrelinfo_extra = lappend(estate->es_resultrelinfo_extra,
+											 rextra);
+
+	for (int i = 0; i < natts; i++)
+	{
+		if (TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_STORED)
+		{
+			Expr	   *expr;
+
+			/* Fetch the GENERATED AS expression tree */
+			expr = (Expr *) build_column_default(rel, i + 1);
+			if (expr == NULL)
+				elog(ERROR, "no generation expression found for column number %d of table \"%s\"",
+					 i + 1, RelationGetRelationName(rel));
+
+			/*
+			 * If it's an update with a known set of update target columns,
+			 * see if we can skip the computation.
+			 */
+			if (updatedCols)
+			{
+				Bitmapset  *attrs_used = NULL;
+
+				pull_varattnos((Node *) expr, 1, &attrs_used);
+
+				if (!bms_overlap(updatedCols, attrs_used))
+					continue;	/* need not update this column */
+			}
+
+			/* No luck, so prepare the expression for execution */
+			resultRelInfo->ri_GeneratedExprs[i] = ExecPrepareExpr(expr, estate);
+			resultRelInfo->ri_NumGeneratedNeeded++;
+
+			/* And mark this column in rextra->ri_extraUpdatedCols */
+			rextra->ri_extraUpdatedCols =
+				bms_add_member(rextra->ri_extraUpdatedCols,
+							   i + 1 - FirstLowInvalidHeapAttributeNumber);
+		}
+	}
+
+	MemoryContextSwitchTo(oldContext);
+}
+
+/*
+ * Compute stored generated columns for a tuple
+ */
+void
+ExecComputeStoredGenerated(ResultRelInfo *resultRelInfo,
+						   EState *estate, TupleTableSlot *slot,
+						   CmdType cmdtype)
+{
+	Relation	rel = resultRelInfo->ri_RelationDesc;
+	TupleDesc	tupdesc = RelationGetDescr(rel);
+	int			natts = tupdesc->natts;
+	ExprContext *econtext = GetPerTupleExprContext(estate);
+	MemoryContext oldContext;
+	Datum	   *values;
+	bool	   *nulls;
+
+	/* We should not be called unless this is true */
+	Assert(tupdesc->constr && tupdesc->constr->has_generated_stored);
+
+	/*
+	 * For relations named directly in the query, ExecInitStoredGenerated
+	 * should have been called already; but this might not have happened yet
+	 * for a partition child rel.  Also, it's convenient for outside callers
+	 * to not have to call ExecInitStoredGenerated explicitly.
+	 */
+	if (resultRelInfo->ri_GeneratedExprs == NULL)
+		ExecInitStoredGenerated(resultRelInfo, estate, cmdtype);
+
+	/*
+	 * If no generated columns have been affected by this change, then skip
+	 * the rest.
+	 */
+	if (resultRelInfo->ri_NumGeneratedNeeded == 0)
+		return;
+
+	oldContext = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
+
+	values = palloc(sizeof(*values) * natts);
+	nulls = palloc(sizeof(*nulls) * natts);
+
+	slot_getallattrs(slot);
+	memcpy(nulls, slot->tts_isnull, sizeof(*nulls) * natts);
+
+	for (int i = 0; i < natts; i++)
+	{
+		Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
+
+		if (resultRelInfo->ri_GeneratedExprs[i])
+		{
+			Datum		val;
+			bool		isnull;
+
+			Assert(attr->attgenerated == ATTRIBUTE_GENERATED_STORED);
+
+			econtext->ecxt_scantuple = slot;
+
+			val = ExecEvalExpr(resultRelInfo->ri_GeneratedExprs[i], econtext, &isnull);
+
+			/*
+			 * We must make a copy of val as we have no guarantees about where
+			 * memory for a pass-by-reference Datum is located.
+			 */
+			if (!isnull)
+				val = datumCopy(val, attr->attbyval, attr->attlen);
+
+			values[i] = val;
+			nulls[i] = isnull;
+		}
+		else
+		{
+			if (!nulls[i])
+				values[i] = datumCopy(slot->tts_values[i], attr->attbyval, attr->attlen);
+		}
+	}
+
+	ExecClearTuple(slot);
+	memcpy(slot->tts_values, values, sizeof(*values) * natts);
+	memcpy(slot->tts_isnull, nulls, sizeof(*nulls) * natts);
+	ExecStoreVirtualTuple(slot);
+	ExecMaterializeSlot(slot);
+
+	MemoryContextSwitchTo(oldContext);
+}
+
+/*
+ * ExecInitInsertProjection
+ *		Do one-time initialization of projection data for INSERT tuples.
+ *
+ * INSERT queries may need a projection to filter out junk attrs in the tlist.
+ *
+ * This is also a convenient place to verify that the
+ * output of an INSERT matches the target table.
+ */
+static void
+ExecInitInsertProjection(ModifyTableState *mtstate,
+						 ResultRelInfo *resultRelInfo)
+{
+	ModifyTable *node = (ModifyTable *) mtstate->ps.plan;
+	Plan	   *subplan = outerPlan(node);
+	EState	   *estate = mtstate->ps.state;
+	List	   *insertTargetList = NIL;
+	bool		need_projection = false;
+	ListCell   *l;
+
+	/* Extract non-junk columns of the subplan's result tlist. */
+	foreach(l, subplan->targetlist)
+	{
+		TargetEntry *tle = (TargetEntry *) lfirst(l);
+
+		if (!tle->resjunk)
+			insertTargetList = lappend(insertTargetList, tle);
+		else
+			need_projection = true;
+	}
+
+	/*
+	 * The junk-free list must produce a tuple suitable for the result
+	 * relation.
+	 */
+	ExecCheckPlanOutput(resultRelInfo->ri_RelationDesc, insertTargetList);
+
+	/* We'll need a slot matching the table's format. */
+	resultRelInfo->ri_newTupleSlot =
+		table_slot_create(resultRelInfo->ri_RelationDesc,
+						  &estate->es_tupleTable);
+
+	/* Build ProjectionInfo if needed (it probably isn't). */
+	if (need_projection)
+	{
+		TupleDesc	relDesc = RelationGetDescr(resultRelInfo->ri_RelationDesc);
+
+		/* need an expression context to do the projection */
+		if (mtstate->ps.ps_ExprContext == NULL)
+			ExecAssignExprContext(estate, &mtstate->ps);
+
+		resultRelInfo->ri_projectNew =
+			ExecBuildProjectionInfo(insertTargetList,
+									mtstate->ps.ps_ExprContext,
+									resultRelInfo->ri_newTupleSlot,
+									&mtstate->ps,
+									relDesc);
+	}
+
+	resultRelInfo->ri_projectNewInfoValid = true;
+}
+
+/*
+ * ExecInitUpdateProjection
+ *		Do one-time initialization of projection data for UPDATE tuples.
+ *
+ * UPDATE always needs a projection, because (1) there's always some junk
+ * attrs, and (2) we may need to merge values of not-updated columns from
+ * the old tuple into the final tuple.  In UPDATE, the tuple arriving from
+ * the subplan contains only new values for the changed columns, plus row
+ * identity info in the junk attrs.
+ *
+ * This is "one-time" for any given result rel, but we might touch more than
+ * one result rel in the course of an inherited UPDATE, and each one needs
+ * its own projection due to possible column order variation.
+ *
+ * This is also a convenient place to verify that the output of an UPDATE
+ * matches the target table (ExecBuildUpdateProjection does that).
+ */
+static void
+ExecInitUpdateProjection(ModifyTableState *mtstate,
+						 ResultRelInfo *resultRelInfo)
+{
+	ModifyTable *node = (ModifyTable *) mtstate->ps.plan;
+	Plan	   *subplan = outerPlan(node);
+	EState	   *estate = mtstate->ps.state;
+	TupleDesc	relDesc = RelationGetDescr(resultRelInfo->ri_RelationDesc);
+	int			whichrel;
+	List	   *updateColnos;
+
+	/*
+	 * Usually, mt_lastResultIndex matches the target rel.  If it happens not
+	 * to, we can get the index the hard way with an integer division.
+	 */
+	whichrel = mtstate->mt_lastResultIndex;
+	if (resultRelInfo != mtstate->resultRelInfo + whichrel)
+	{
+		whichrel = resultRelInfo - mtstate->resultRelInfo;
+		Assert(whichrel >= 0 && whichrel < mtstate->mt_nrels);
+	}
+
+	updateColnos = (List *) list_nth(node->updateColnosLists, whichrel);
+
+	/*
+	 * For UPDATE, we use the old tuple to fill up missing values in the tuple
+	 * produced by the subplan to get the new tuple.  We need two slots, both
+	 * matching the table's desired format.
+	 */
+	resultRelInfo->ri_oldTupleSlot =
+		table_slot_create(resultRelInfo->ri_RelationDesc,
+						  &estate->es_tupleTable);
+	resultRelInfo->ri_newTupleSlot =
+		table_slot_create(resultRelInfo->ri_RelationDesc,
+						  &estate->es_tupleTable);
+
+	/* need an expression context to do the projection */
+	if (mtstate->ps.ps_ExprContext == NULL)
+		ExecAssignExprContext(estate, &mtstate->ps);
+
+	resultRelInfo->ri_projectNew =
+		ExecBuildUpdateProjection(subplan->targetlist,
+								  false,	/* subplan did the evaluation */
+								  updateColnos,
+								  relDesc,
+								  mtstate->ps.ps_ExprContext,
+								  resultRelInfo->ri_newTupleSlot,
+								  &mtstate->ps);
+
+	resultRelInfo->ri_projectNewInfoValid = true;
+}
+
+/*
+ * ExecGetInsertNewTuple
+ *		This prepares a "new" tuple ready to be inserted into given result
+ *		relation, by removing any junk columns of the plan's output tuple
+ *		and (if necessary) coercing the tuple to the right tuple format.
+ */
+static TupleTableSlot *
+ExecGetInsertNewTuple(ResultRelInfo *relinfo,
+					  TupleTableSlot *planSlot)
+{
+	ProjectionInfo *newProj = relinfo->ri_projectNew;
+	ExprContext *econtext;
+
+	/*
+	 * If there's no projection to be done, just make sure the slot is of the
+	 * right type for the target rel.  If the planSlot is the right type we
+	 * can use it as-is, else copy the data into ri_newTupleSlot.
+	 */
+	if (newProj == NULL)
+	{
+		if (relinfo->ri_newTupleSlot->tts_ops != planSlot->tts_ops)
+		{
+			ExecCopySlot(relinfo->ri_newTupleSlot, planSlot);
+			return relinfo->ri_newTupleSlot;
+		}
+		else
+			return planSlot;
+	}
+
+	/*
+	 * Else project; since the projection output slot is ri_newTupleSlot, this
+	 * will also fix any slot-type problem.
+	 *
+	 * Note: currently, this is dead code, because INSERT cases don't receive
+	 * any junk columns so there's never a projection to be done.
+	 */
+	econtext = newProj->pi_exprContext;
+	econtext->ecxt_outertuple = planSlot;
+	return ExecProject(newProj);
+}
+
+/*
+ * ExecGetUpdateNewTuple
+ *		This prepares a "new" tuple by combining an UPDATE subplan's output
+ *		tuple (which contains values of changed columns) with unchanged
+ *		columns taken from the old tuple.
+ *
+ * The subplan tuple might also contain junk columns, which are ignored.
+ * Note that the projection also ensures we have a slot of the right type.
+ */
+TupleTableSlot *
+ExecGetUpdateNewTuple(ResultRelInfo *relinfo,
+					  TupleTableSlot *planSlot,
+					  TupleTableSlot *oldSlot)
+{
+	ProjectionInfo *newProj = relinfo->ri_projectNew;
+	ExprContext *econtext;
+
+	/* Use a few extra Asserts to protect against outside callers */
+	Assert(relinfo->ri_projectNewInfoValid);
+	Assert(planSlot != NULL && !TTS_EMPTY(planSlot));
+	Assert(oldSlot != NULL && !TTS_EMPTY(oldSlot));
+
+	econtext = newProj->pi_exprContext;
+	econtext->ecxt_outertuple = planSlot;
+	econtext->ecxt_scantuple = oldSlot;
+	return ExecProject(newProj);
+}
+
+/* ----------------------------------------------------------------
+ *		ExecInsert
+ *
+ *		For INSERT, we have to insert the tuple into the target relation
+ *		(or partition thereof) and insert appropriate tuples into the index
+ *		relations.
+ *
+ *		slot contains the new tuple value to be stored.
+ *
+ *		Returns RETURNING result if any, otherwise NULL.
+ *		*inserted_tuple is the tuple that's effectively inserted;
+ *		*inserted_destrel is the relation where it was inserted.
+ *		These are only set on success.
+ *
+ *		This may change the currently active tuple conversion map in
+ *		mtstate->mt_transition_capture, so the callers must take care to
+ *		save the previous value to avoid losing track of it.
+ * ----------------------------------------------------------------
+ */
+static TupleTableSlot *
+ExecInsert(ModifyTableContext *context,
+		   ResultRelInfo *resultRelInfo,
+		   TupleTableSlot *slot,
+		   bool canSetTag,
+		   TupleTableSlot **inserted_tuple,
+		   ResultRelInfo **insert_destrel)
+{
+	ModifyTableState *mtstate = context->mtstate;
+	EState	   *estate = context->estate;
+	Relation	resultRelationDesc;
+	List	   *recheckIndexes = NIL;
+	TupleTableSlot *planSlot = context->planSlot;
+	TupleTableSlot *result = NULL;
+	TransitionCaptureState *ar_insert_trig_tcs;
+	ModifyTable *node = (ModifyTable *) mtstate->ps.plan;
+	OnConflictAction onconflict = node->onConflictAction;
+	PartitionTupleRouting *proute = mtstate->mt_partition_tuple_routing;
+	MemoryContext oldContext;
+
+	/*
+	 * If the input result relation is a partitioned table, find the leaf
+	 * partition to insert the tuple into.
+	 */
+	if (proute)
+	{
+		ResultRelInfo *partRelInfo;
+
+		slot = ExecPrepareTupleRouting(mtstate, estate, proute,
+									   resultRelInfo, slot,
+									   &partRelInfo);
+		resultRelInfo = partRelInfo;
+	}
+
+	ExecMaterializeSlot(slot);
+
+	resultRelationDesc = resultRelInfo->ri_RelationDesc;
+
+	/*
+	 * Open the table's indexes, if we have not done so already, so that we
+	 * can add new index entries for the inserted tuple.
+	 */
+	if (resultRelationDesc->rd_rel->relhasindex &&
+		resultRelInfo->ri_IndexRelationDescs == NULL)
+		ExecOpenIndices(resultRelInfo, onconflict != ONCONFLICT_NONE);
+
+	/*
+	 * BEFORE ROW INSERT Triggers.
+	 *
+	 * Note: We fire BEFORE ROW TRIGGERS for every attempted insertion in an
+	 * INSERT ... ON CONFLICT statement.  We cannot check for constraint
+	 * violations before firing these triggers, because they can change the
+	 * values to insert.  Also, they can run arbitrary user-defined code with
+	 * side-effects that we can't cancel by just not inserting the tuple.
+	 */
+	if (resultRelInfo->ri_TrigDesc &&
+		resultRelInfo->ri_TrigDesc->trig_insert_before_row)
+	{
+		/* Flush any pending inserts, so rows are visible to the triggers */
+		if (estate->es_insert_pending_result_relations != NIL)
+			ExecPendingInserts(estate);
+
+		if (!ExecBRInsertTriggers(estate, resultRelInfo, slot))
+			return NULL;		/* "do nothing" */
+	}
+
+	/* INSTEAD OF ROW INSERT Triggers */
+	if (resultRelInfo->ri_TrigDesc &&
+		resultRelInfo->ri_TrigDesc->trig_insert_instead_row)
+	{
+		if (!ExecIRInsertTriggers(estate, resultRelInfo, slot))
+			return NULL;		/* "do nothing" */
+	}
+	else if (resultRelInfo->ri_FdwRoutine)
+	{
+		/*
+		 * GENERATED expressions might reference the tableoid column, so
+		 * (re-)initialize tts_tableOid before evaluating them.
+		 */
+		slot->tts_tableOid = RelationGetRelid(resultRelInfo->ri_RelationDesc);
+
+		/*
+		 * Compute stored generated columns
+		 */
+		if (resultRelationDesc->rd_att->constr &&
+			resultRelationDesc->rd_att->constr->has_generated_stored)
+			ExecComputeStoredGenerated(resultRelInfo, estate, slot,
+									   CMD_INSERT);
+
+		/*
+		 * If the FDW supports batching, and batching is requested, accumulate
+		 * rows and insert them in batches. Otherwise use the per-row inserts.
+		 */
+		if (resultRelInfo->ri_BatchSize > 1)
+		{
+			bool		flushed = false;
+
+			/*
+			 * When we've reached the desired batch size, perform the
+			 * insertion.
+			 */
+			if (resultRelInfo->ri_NumSlots == resultRelInfo->ri_BatchSize)
+			{
+				ExecBatchInsert(mtstate, resultRelInfo,
+								resultRelInfo->ri_Slots,
+								resultRelInfo->ri_PlanSlots,
+								resultRelInfo->ri_NumSlots,
+								estate, canSetTag);
+				flushed = true;
+			}
+
+			oldContext = MemoryContextSwitchTo(estate->es_query_cxt);
+
+			if (resultRelInfo->ri_Slots == NULL)
+			{
+				resultRelInfo->ri_Slots = palloc(sizeof(TupleTableSlot *) *
+												 resultRelInfo->ri_BatchSize);
+				resultRelInfo->ri_PlanSlots = palloc(sizeof(TupleTableSlot *) *
+													 resultRelInfo->ri_BatchSize);
+			}
+
+			/*
+			 * Initialize the batch slots. We don't know how many slots will
+			 * be needed, so we initialize them as the batch grows, and we
+			 * keep them across batches. To mitigate an inefficiency in how
+			 * resource owner handles objects with many references (as with
+			 * many slots all referencing the same tuple descriptor) we copy
+			 * the appropriate tuple descriptor for each slot.
+			 */
+			if (resultRelInfo->ri_NumSlots >= resultRelInfo->ri_NumSlotsInitialized)
+			{
+				TupleDesc	tdesc = CreateTupleDescCopy(slot->tts_tupleDescriptor);
+				TupleDesc	plan_tdesc =
+				CreateTupleDescCopy(planSlot->tts_tupleDescriptor);
+
+				resultRelInfo->ri_Slots[resultRelInfo->ri_NumSlots] =
+					MakeSingleTupleTableSlot(tdesc, slot->tts_ops);
+
+				resultRelInfo->ri_PlanSlots[resultRelInfo->ri_NumSlots] =
+					MakeSingleTupleTableSlot(plan_tdesc, planSlot->tts_ops);
+
+				/* remember how many batch slots we initialized */
+				resultRelInfo->ri_NumSlotsInitialized++;
+			}
+
+			ExecCopySlot(resultRelInfo->ri_Slots[resultRelInfo->ri_NumSlots],
+						 slot);
+
+			ExecCopySlot(resultRelInfo->ri_PlanSlots[resultRelInfo->ri_NumSlots],
+						 planSlot);
+
+			/*
+			 * If these are the first tuples stored in the buffers, add the
+			 * target rel and the mtstate to the
+			 * es_insert_pending_result_relations and
+			 * es_insert_pending_modifytables lists respectively, execpt in
+			 * the case where flushing was done above, in which case they
+			 * would already have been added to the lists, so no need to do
+			 * this.
+			 */
+			if (resultRelInfo->ri_NumSlots == 0 && !flushed)
+			{
+				Assert(!list_member_ptr(estate->es_insert_pending_result_relations,
+										resultRelInfo));
+				estate->es_insert_pending_result_relations =
+					lappend(estate->es_insert_pending_result_relations,
+							resultRelInfo);
+				estate->es_insert_pending_modifytables =
+					lappend(estate->es_insert_pending_modifytables, mtstate);
+			}
+			Assert(list_member_ptr(estate->es_insert_pending_result_relations,
+								   resultRelInfo));
+
+			resultRelInfo->ri_NumSlots++;
+
+			MemoryContextSwitchTo(oldContext);
+
+			return NULL;
+		}
+
+		/*
+		 * insert into foreign table: let the FDW do it
+		 */
+		slot = resultRelInfo->ri_FdwRoutine->ExecForeignInsert(estate,
+															   resultRelInfo,
+															   slot,
+															   planSlot);
+
+		if (slot == NULL)		/* "do nothing" */
+			return NULL;
+
+		/*
+		 * AFTER ROW Triggers or RETURNING expressions might reference the
+		 * tableoid column, so (re-)initialize tts_tableOid before evaluating
+		 * them.  (This covers the case where the FDW replaced the slot.)
+		 */
+		slot->tts_tableOid = RelationGetRelid(resultRelInfo->ri_RelationDesc);
+	}
+	else
+	{
+		WCOKind		wco_kind;
+
+		/*
+		 * Constraints and GENERATED expressions might reference the tableoid
+		 * column, so (re-)initialize tts_tableOid before evaluating them.
+		 */
+		slot->tts_tableOid = RelationGetRelid(resultRelationDesc);
+
+		/*
+		 * Compute stored generated columns
+		 */
+		if (resultRelationDesc->rd_att->constr &&
+			resultRelationDesc->rd_att->constr->has_generated_stored)
+			ExecComputeStoredGenerated(resultRelInfo, estate, slot,
+									   CMD_INSERT);
+
+		/*
+		 * Check any RLS WITH CHECK policies.
+		 *
+		 * Normally we should check INSERT policies. But if the insert is the
+		 * result of a partition key update that moved the tuple to a new
+		 * partition, we should instead check UPDATE policies, because we are
+		 * executing policies defined on the target table, and not those
+		 * defined on the child partitions.
+		 *
+		 * If we're running MERGE, we refer to the action that we're executing
+		 * to know if we're doing an INSERT or UPDATE to a partition table.
+		 */
+		if (mtstate->operation == CMD_UPDATE)
+			wco_kind = WCO_RLS_UPDATE_CHECK;
+		else if (mtstate->operation == CMD_MERGE)
+			wco_kind = (context->relaction->mas_action->commandType == CMD_UPDATE) ?
+				WCO_RLS_UPDATE_CHECK : WCO_RLS_INSERT_CHECK;
+		else
+			wco_kind = WCO_RLS_INSERT_CHECK;
+
+		/*
+		 * ExecWithCheckOptions() will skip any WCOs which are not of the kind
+		 * we are looking for at this point.
+		 */
+		if (resultRelInfo->ri_WithCheckOptions != NIL)
+			ExecWithCheckOptions(wco_kind, resultRelInfo, slot, estate);
+
+		/*
+		 * Check the constraints of the tuple.
+		 */
+		if (resultRelationDesc->rd_att->constr)
+			ExecConstraints(resultRelInfo, slot, estate);
+
+		/*
+		 * Also check the tuple against the partition constraint, if there is
+		 * one; except that if we got here via tuple-routing, we don't need to
+		 * if there's no BR trigger defined on the partition.
+		 */
+		if (resultRelationDesc->rd_rel->relispartition &&
+			(resultRelInfo->ri_RootResultRelInfo == NULL ||
+			 (resultRelInfo->ri_TrigDesc &&
+			  resultRelInfo->ri_TrigDesc->trig_insert_before_row)))
+			ExecPartitionCheck(resultRelInfo, slot, estate, true);
+
+		if (onconflict != ONCONFLICT_NONE && resultRelInfo->ri_NumIndices > 0)
+		{
+			/* Perform a speculative insertion. */
+			uint32		specToken;
+			ItemPointerData conflictTid;
+			bool		specConflict;
+			List	   *arbiterIndexes;
+
+			arbiterIndexes = resultRelInfo->ri_onConflictArbiterIndexes;
+
+			/*
+			 * Do a non-conclusive check for conflicts first.
+			 *
+			 * We're not holding any locks yet, so this doesn't guarantee that
+			 * the later insert won't conflict.  But it avoids leaving behind
+			 * a lot of canceled speculative insertions, if you run a lot of
+			 * INSERT ON CONFLICT statements that do conflict.
+			 *
+			 * We loop back here if we find a conflict below, either during
+			 * the pre-check, or when we re-check after inserting the tuple
+			 * speculatively.  Better allow interrupts in case some bug makes
+			 * this an infinite loop.
+			 */
+	vlock:
+			CHECK_FOR_INTERRUPTS();
+			specConflict = false;
+			if (!ExecCheckIndexConstraints(resultRelInfo, slot, estate,
+										   &conflictTid, arbiterIndexes))
+			{
+				/* committed conflict tuple found */
+				if (onconflict == ONCONFLICT_UPDATE)
+				{
+					/*
+					 * In case of ON CONFLICT DO UPDATE, execute the UPDATE
+					 * part.  Be prepared to retry if the UPDATE fails because
+					 * of another concurrent UPDATE/DELETE to the conflict
+					 * tuple.
+					 */
+					TupleTableSlot *returning = NULL;
+
+					if (ExecOnConflictUpdate(context, resultRelInfo,
+											 &conflictTid, slot, canSetTag,
+											 &returning))
+					{
+						InstrCountTuples2(&mtstate->ps, 1);
+						return returning;
+					}
+					else
+						goto vlock;
+				}
+				else
+				{
+					/*
+					 * In case of ON CONFLICT DO NOTHING, do nothing. However,
+					 * verify that the tuple is visible to the executor's MVCC
+					 * snapshot at higher isolation levels.
+					 *
+					 * Using ExecGetReturningSlot() to store the tuple for the
+					 * recheck isn't that pretty, but we can't trivially use
+					 * the input slot, because it might not be of a compatible
+					 * type. As there's no conflicting usage of
+					 * ExecGetReturningSlot() in the DO NOTHING case...
+					 */
+					Assert(onconflict == ONCONFLICT_NOTHING);
+					ExecCheckTIDVisible(estate, resultRelInfo, &conflictTid,
+										ExecGetReturningSlot(estate, resultRelInfo));
+					InstrCountTuples2(&mtstate->ps, 1);
+					return NULL;
+				}
+			}
+
+			/*
+			 * Before we start insertion proper, acquire our "speculative
+			 * insertion lock".  Others can use that to wait for us to decide
+			 * if we're going to go ahead with the insertion, instead of
+			 * waiting for the whole transaction to complete.
+			 */
+			specToken = SpeculativeInsertionLockAcquire(GetCurrentTransactionId());
+
+			/* insert the tuple, with the speculative token */
+			table_tuple_insert_speculative(resultRelationDesc, slot,
+										   estate->es_output_cid,
+										   0,
+										   NULL,
+										   specToken);
+
+			/* insert index entries for tuple */
+			recheckIndexes = ExecInsertIndexTuples(resultRelInfo,
+												   slot, estate, false, true,
+												   &specConflict,
+												   arbiterIndexes);
+
+			/* adjust the tuple's state accordingly */
+			table_tuple_complete_speculative(resultRelationDesc, slot,
+											 specToken, !specConflict);
+
+			/*
+			 * Wake up anyone waiting for our decision.  They will re-check
+			 * the tuple, see that it's no longer speculative, and wait on our
+			 * XID as if this was a regularly inserted tuple all along.  Or if
+			 * we killed the tuple, they will see it's dead, and proceed as if
+			 * the tuple never existed.
+			 */
+			SpeculativeInsertionLockRelease(GetCurrentTransactionId());
+
+			/*
+			 * If there was a conflict, start from the beginning.  We'll do
+			 * the pre-check again, which will now find the conflicting tuple
+			 * (unless it aborts before we get there).
+			 */
+			if (specConflict)
+			{
+				list_free(recheckIndexes);
+				goto vlock;
+			}
+
+			/* Since there was no insertion conflict, we're done */
+		}
+		else
+		{
+			/* insert the tuple normally */
+			table_tuple_insert(resultRelationDesc, slot,
+							   estate->es_output_cid,
+							   0, NULL);
+
+			/* insert index entries for tuple */
+			if (resultRelInfo->ri_NumIndices > 0)
+				recheckIndexes = ExecInsertIndexTuples(resultRelInfo,
+													   slot, estate, false,
+													   false, NULL, NIL);
+		}
+	}
+
+	if (canSetTag)
+		(estate->es_processed)++;
+
+	/*
+	 * If this insert is the result of a partition key update that moved the
+	 * tuple to a new partition, put this row into the transition NEW TABLE,
+	 * if there is one. We need to do this separately for DELETE and INSERT
+	 * because they happen on different tables.
+	 */
+	ar_insert_trig_tcs = mtstate->mt_transition_capture;
+	if (mtstate->operation == CMD_UPDATE && mtstate->mt_transition_capture
+		&& mtstate->mt_transition_capture->tcs_update_new_table)
+	{
+		ExecARUpdateTriggers(estate, resultRelInfo,
+							 NULL, NULL,
+							 NULL,
+							 NULL,
+							 slot,
+							 NULL,
+							 mtstate->mt_transition_capture,
+							 false);
+
+		/*
+		 * We've already captured the NEW TABLE row, so make sure any AR
+		 * INSERT trigger fired below doesn't capture it again.
+		 */
+		ar_insert_trig_tcs = NULL;
+	}
+
+	/* AFTER ROW INSERT Triggers */
+	ExecARInsertTriggers(estate, resultRelInfo, slot, recheckIndexes,
+						 ar_insert_trig_tcs);
+
+	list_free(recheckIndexes);
+
+	/*
+	 * Check any WITH CHECK OPTION constraints from parent views.  We are
+	 * required to do this after testing all constraints and uniqueness
+	 * violations per the SQL spec, so we do it after actually inserting the
+	 * record into the heap and all indexes.
+	 *
+	 * ExecWithCheckOptions will elog(ERROR) if a violation is found, so the
+	 * tuple will never be seen, if it violates the WITH CHECK OPTION.
+	 *
+	 * ExecWithCheckOptions() will skip any WCOs which are not of the kind we
+	 * are looking for at this point.
+	 */
+	if (resultRelInfo->ri_WithCheckOptions != NIL)
+		ExecWithCheckOptions(WCO_VIEW_CHECK, resultRelInfo, slot, estate);
+
+	/* Process RETURNING if present */
+	if (resultRelInfo->ri_projectReturning)
+		result = ExecProcessReturning(resultRelInfo, slot, planSlot);
+
+	if (inserted_tuple)
+		*inserted_tuple = slot;
+	if (insert_destrel)
+		*insert_destrel = resultRelInfo;
+
+	return result;
+}
+
+/* ----------------------------------------------------------------
+ *		ExecBatchInsert
+ *
+ *		Insert multiple tuples in an efficient way.
+ *		Currently, this handles inserting into a foreign table without
+ *		RETURNING clause.
+ * ----------------------------------------------------------------
+ */
+static void
+ExecBatchInsert(ModifyTableState *mtstate,
+				ResultRelInfo *resultRelInfo,
+				TupleTableSlot **slots,
+				TupleTableSlot **planSlots,
+				int numSlots,
+				EState *estate,
+				bool canSetTag)
+{
+	int			i;
+	int			numInserted = numSlots;
+	TupleTableSlot *slot = NULL;
+	TupleTableSlot **rslots;
+
+	/*
+	 * insert into foreign table: let the FDW do it
+	 */
+	rslots = resultRelInfo->ri_FdwRoutine->ExecForeignBatchInsert(estate,
+																  resultRelInfo,
+																  slots,
+																  planSlots,
+																  &numInserted);
+
+	for (i = 0; i < numInserted; i++)
+	{
+		slot = rslots[i];
+
+		/*
+		 * AFTER ROW Triggers might reference the tableoid column, so
+		 * (re-)initialize tts_tableOid before evaluating them.
+		 */
+		slot->tts_tableOid = RelationGetRelid(resultRelInfo->ri_RelationDesc);
+
+		/* AFTER ROW INSERT Triggers */
+		ExecARInsertTriggers(estate, resultRelInfo, slot, NIL,
+							 mtstate->mt_transition_capture);
+
+		/*
+		 * Check any WITH CHECK OPTION constraints from parent views.  See the
+		 * comment in ExecInsert.
+		 */
+		if (resultRelInfo->ri_WithCheckOptions != NIL)
+			ExecWithCheckOptions(WCO_VIEW_CHECK, resultRelInfo, slot, estate);
+	}
+
+	if (canSetTag && numInserted > 0)
+		estate->es_processed += numInserted;
+
+	/* Clean up all the slots, ready for the next batch */
+	for (i = 0; i < numSlots; i++)
+	{
+		ExecClearTuple(slots[i]);
+		ExecClearTuple(planSlots[i]);
+	}
+	resultRelInfo->ri_NumSlots = 0;
+}
+
+/*
+ * ExecPendingInserts -- flushes all pending inserts to the foreign tables
+ */
+static void
+ExecPendingInserts(EState *estate)
+{
+	ListCell   *l1,
+			   *l2;
+
+	forboth(l1, estate->es_insert_pending_result_relations,
+			l2, estate->es_insert_pending_modifytables)
+	{
+		ResultRelInfo *resultRelInfo = (ResultRelInfo *) lfirst(l1);
+		ModifyTableState *mtstate = (ModifyTableState *) lfirst(l2);
+
+		Assert(mtstate);
+		ExecBatchInsert(mtstate, resultRelInfo,
+						resultRelInfo->ri_Slots,
+						resultRelInfo->ri_PlanSlots,
+						resultRelInfo->ri_NumSlots,
+						estate, mtstate->canSetTag);
+	}
+
+	list_free(estate->es_insert_pending_result_relations);
+	list_free(estate->es_insert_pending_modifytables);
+	estate->es_insert_pending_result_relations = NIL;
+	estate->es_insert_pending_modifytables = NIL;
+}
+
+/*
+ * ExecDeletePrologue -- subroutine for ExecDelete
+ *
+ * Prepare executor state for DELETE.  Actually, the only thing we have to do
+ * here is execute BEFORE ROW triggers.  We return false if one of them makes
+ * the delete a no-op; otherwise, return true.
+ */
+static bool
+ExecDeletePrologue(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
+				   ItemPointer tupleid, HeapTuple oldtuple,
+				   TupleTableSlot **epqreturnslot, TM_Result *result)
+{
+	if (result)
+		*result = TM_Ok;
+
+	/* BEFORE ROW DELETE triggers */
+	if (resultRelInfo->ri_TrigDesc &&
+		resultRelInfo->ri_TrigDesc->trig_delete_before_row)
+	{
+		/* Flush any pending inserts, so rows are visible to the triggers */
+		if (context->estate->es_insert_pending_result_relations != NIL)
+			ExecPendingInserts(context->estate);
+
+		return ExecBRDeleteTriggersNew(context->estate, context->epqstate,
+									   resultRelInfo, tupleid, oldtuple,
+									   epqreturnslot, result, &context->tmfd);
+	}
+
+	return true;
+}
+
+/*
+ * ExecDeleteAct -- subroutine for ExecDelete
+ *
+ * Actually delete the tuple from a plain table.
+ *
+ * Caller is in charge of doing EvalPlanQual as necessary
+ */
+static TM_Result
+ExecDeleteAct(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
+			  ItemPointer tupleid, bool changingPart)
+{
+	EState	   *estate = context->estate;
+
+	return table_tuple_delete(resultRelInfo->ri_RelationDesc, tupleid,
+							  estate->es_output_cid,
+							  estate->es_snapshot,
+							  estate->es_crosscheck_snapshot,
+							  true /* wait for commit */ ,
+							  &context->tmfd,
+							  changingPart);
+}
+
+/*
+ * ExecDeleteEpilogue -- subroutine for ExecDelete
+ *
+ * Closing steps of tuple deletion; this invokes AFTER FOR EACH ROW triggers,
+ * including the UPDATE triggers if the deletion is being done as part of a
+ * cross-partition tuple move.
+ */
+static void
+ExecDeleteEpilogue(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
+				   ItemPointer tupleid, HeapTuple oldtuple, bool changingPart)
+{
+	ModifyTableState *mtstate = context->mtstate;
+	EState	   *estate = context->estate;
+	TransitionCaptureState *ar_delete_trig_tcs;
+
+	/*
+	 * If this delete is the result of a partition key update that moved the
+	 * tuple to a new partition, put this row into the transition OLD TABLE,
+	 * if there is one. We need to do this separately for DELETE and INSERT
+	 * because they happen on different tables.
+	 */
+	ar_delete_trig_tcs = mtstate->mt_transition_capture;
+	if (mtstate->operation == CMD_UPDATE && mtstate->mt_transition_capture &&
+		mtstate->mt_transition_capture->tcs_update_old_table)
+	{
+		ExecARUpdateTriggers(estate, resultRelInfo,
+							 NULL, NULL,
+							 tupleid, oldtuple,
+							 NULL, NULL, mtstate->mt_transition_capture,
+							 false);
+
+		/*
+		 * We've already captured the OLD TABLE row, so make sure any AR
+		 * DELETE trigger fired below doesn't capture it again.
+		 */
+		ar_delete_trig_tcs = NULL;
+	}
+
+	/* AFTER ROW DELETE Triggers */
+	ExecARDeleteTriggers(estate, resultRelInfo, tupleid, oldtuple,
+						 ar_delete_trig_tcs, changingPart);
+}
+
+/* ----------------------------------------------------------------
+ *		ExecDelete
+ *
+ *		DELETE is like UPDATE, except that we delete the tuple and no
+ *		index modifications are needed.
+ *
+ *		When deleting from a table, tupleid identifies the tuple to
+ *		delete and oldtuple is NULL.  When deleting from a view,
+ *		oldtuple is passed to the INSTEAD OF triggers and identifies
+ *		what to delete, and tupleid is invalid.  When deleting from a
+ *		foreign table, tupleid is invalid; the FDW has to figure out
+ *		which row to delete using data from the planSlot.  oldtuple is
+ *		passed to foreign table triggers; it is NULL when the foreign
+ *		table has no relevant triggers.  We use tupleDeleted to indicate
+ *		whether the tuple is actually deleted, callers can use it to
+ *		decide whether to continue the operation.  When this DELETE is a
+ *		part of an UPDATE of partition-key, then the slot returned by
+ *		EvalPlanQual() is passed back using output parameter epqreturnslot.
+ *
+ *		Returns RETURNING result if any, otherwise NULL.
+ * ----------------------------------------------------------------
+ */
+static TupleTableSlot *
+ExecDelete(ModifyTableContext *context,
+		   ResultRelInfo *resultRelInfo,
+		   ItemPointer tupleid,
+		   HeapTuple oldtuple,
+		   bool processReturning,
+		   bool changingPart,
+		   bool canSetTag,
+		   bool *tupleDeleted,
+		   TupleTableSlot **epqreturnslot)
+{
+	EState	   *estate = context->estate;
+	Relation	resultRelationDesc = resultRelInfo->ri_RelationDesc;
+	TupleTableSlot *slot = NULL;
+	TM_Result	result;
+
+	if (tupleDeleted)
+		*tupleDeleted = false;
+
+	/*
+	 * Prepare for the delete.  This includes BEFORE ROW triggers, so we're
+	 * done if it says we are.
+	 */
+	if (!ExecDeletePrologue(context, resultRelInfo, tupleid, oldtuple,
+							epqreturnslot, NULL))
+		return NULL;
+
+	/* INSTEAD OF ROW DELETE Triggers */
+	if (resultRelInfo->ri_TrigDesc &&
+		resultRelInfo->ri_TrigDesc->trig_delete_instead_row)
+	{
+		bool		dodelete;
+
+		Assert(oldtuple != NULL);
+		dodelete = ExecIRDeleteTriggers(estate, resultRelInfo, oldtuple);
+
+		if (!dodelete)			/* "do nothing" */
+			return NULL;
+	}
+	else if (resultRelInfo->ri_FdwRoutine)
+	{
+		/*
+		 * delete from foreign table: let the FDW do it
+		 *
+		 * We offer the returning slot as a place to store RETURNING data,
+		 * although the FDW can return some other slot if it wants.
+		 */
+		slot = ExecGetReturningSlot(estate, resultRelInfo);
+		slot = resultRelInfo->ri_FdwRoutine->ExecForeignDelete(estate,
+															   resultRelInfo,
+															   slot,
+															   context->planSlot);
+
+		if (slot == NULL)		/* "do nothing" */
+			return NULL;
+
+		/*
+		 * RETURNING expressions might reference the tableoid column, so
+		 * (re)initialize tts_tableOid before evaluating them.
+		 */
+		if (TTS_EMPTY(slot))
+			ExecStoreAllNullTuple(slot);
+
+		slot->tts_tableOid = RelationGetRelid(resultRelationDesc);
+	}
+	else
+	{
+		/*
+		 * delete the tuple
+		 *
+		 * Note: if context->estate->es_crosscheck_snapshot isn't
+		 * InvalidSnapshot, we check that the row to be deleted is visible to
+		 * that snapshot, and throw a can't-serialize error if not. This is a
+		 * special-case behavior needed for referential integrity updates in
+		 * transaction-snapshot mode transactions.
+		 */
+ldelete:;
+		result = ExecDeleteAct(context, resultRelInfo, tupleid, changingPart);
+
+		switch (result)
+		{
+			case TM_SelfModified:
+
+				/*
+				 * The target tuple was already updated or deleted by the
+				 * current command, or by a later command in the current
+				 * transaction.  The former case is possible in a join DELETE
+				 * where multiple tuples join to the same target tuple. This
+				 * is somewhat questionable, but Postgres has always allowed
+				 * it: we just ignore additional deletion attempts.
+				 *
+				 * The latter case arises if the tuple is modified by a
+				 * command in a BEFORE trigger, or perhaps by a command in a
+				 * volatile function used in the query.  In such situations we
+				 * should not ignore the deletion, but it is equally unsafe to
+				 * proceed.  We don't want to discard the original DELETE
+				 * while keeping the triggered actions based on its deletion;
+				 * and it would be no better to allow the original DELETE
+				 * while discarding updates that it triggered.  The row update
+				 * carries some information that might be important according
+				 * to business rules; so throwing an error is the only safe
+				 * course.
+				 *
+				 * If a trigger actually intends this type of interaction, it
+				 * can re-execute the DELETE and then return NULL to cancel
+				 * the outer delete.
+				 */
+				if (context->tmfd.cmax != estate->es_output_cid)
+					ereport(ERROR,
+							(errcode(ERRCODE_TRIGGERED_DATA_CHANGE_VIOLATION),
+							 errmsg("tuple to be deleted was already modified by an operation triggered by the current command"),
+							 errhint("Consider using an AFTER trigger instead of a BEFORE trigger to propagate changes to other rows.")));
+
+				/* Else, already deleted by self; nothing to do */
+				return NULL;
+
+			case TM_Ok:
+				break;
+
+			case TM_Updated:
+				{
+					TupleTableSlot *inputslot;
+					TupleTableSlot *epqslot;
+
+					if (IsolationUsesXactSnapshot())
+						ereport(ERROR,
+								(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+								 errmsg("could not serialize access due to concurrent update")));
+
+					/*
+					 * Already know that we're going to need to do EPQ, so
+					 * fetch tuple directly into the right slot.
+					 */
+					EvalPlanQualBegin(context->epqstate);
+					inputslot = EvalPlanQualSlot(context->epqstate, resultRelationDesc,
+												 resultRelInfo->ri_RangeTableIndex);
+
+					result = table_tuple_lock(resultRelationDesc, tupleid,
+											  estate->es_snapshot,
+											  inputslot, estate->es_output_cid,
+											  LockTupleExclusive, LockWaitBlock,
+											  TUPLE_LOCK_FLAG_FIND_LAST_VERSION,
+											  &context->tmfd);
+
+					switch (result)
+					{
+						case TM_Ok:
+							Assert(context->tmfd.traversed);
+							epqslot = EvalPlanQual(context->epqstate,
+												   resultRelationDesc,
+												   resultRelInfo->ri_RangeTableIndex,
+												   inputslot);
+							if (TupIsNull(epqslot))
+								/* Tuple not passing quals anymore, exiting... */
+								return NULL;
+
+							/*
+							 * If requested, skip delete and pass back the
+							 * updated row.
+							 */
+							if (epqreturnslot)
+							{
+								*epqreturnslot = epqslot;
+								return NULL;
+							}
+							else
+								goto ldelete;
+
+						case TM_SelfModified:
+
+							/*
+							 * This can be reached when following an update
+							 * chain from a tuple updated by another session,
+							 * reaching a tuple that was already updated in
+							 * this transaction. If previously updated by this
+							 * command, ignore the delete, otherwise error
+							 * out.
+							 *
+							 * See also TM_SelfModified response to
+							 * table_tuple_delete() above.
+							 */
+							if (context->tmfd.cmax != estate->es_output_cid)
+								ereport(ERROR,
+										(errcode(ERRCODE_TRIGGERED_DATA_CHANGE_VIOLATION),
+										 errmsg("tuple to be deleted was already modified by an operation triggered by the current command"),
+										 errhint("Consider using an AFTER trigger instead of a BEFORE trigger to propagate changes to other rows.")));
+							return NULL;
+
+						case TM_Deleted:
+							/* tuple already deleted; nothing to do */
+							return NULL;
+
+						default:
+
+							/*
+							 * TM_Invisible should be impossible because we're
+							 * waiting for updated row versions, and would
+							 * already have errored out if the first version
+							 * is invisible.
+							 *
+							 * TM_Updated should be impossible, because we're
+							 * locking the latest version via
+							 * TUPLE_LOCK_FLAG_FIND_LAST_VERSION.
+							 */
+							elog(ERROR, "unexpected table_tuple_lock status: %u",
+								 result);
+							return NULL;
+					}
+
+					Assert(false);
+					break;
+				}
+
+			case TM_Deleted:
+				if (IsolationUsesXactSnapshot())
+					ereport(ERROR,
+							(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+							 errmsg("could not serialize access due to concurrent delete")));
+				/* tuple already deleted; nothing to do */
+				return NULL;
+
+			default:
+				elog(ERROR, "unrecognized table_tuple_delete status: %u",
+					 result);
+				return NULL;
+		}
+
+		/*
+		 * Note: Normally one would think that we have to delete index tuples
+		 * associated with the heap tuple now...
+		 *
+		 * ... but in POSTGRES, we have no need to do this because VACUUM will
+		 * take care of it later.  We can't delete index tuples immediately
+		 * anyway, since the tuple is still visible to other transactions.
+		 */
+	}
+
+	if (canSetTag)
+		(estate->es_processed)++;
+
+	/* Tell caller that the delete actually happened. */
+	if (tupleDeleted)
+		*tupleDeleted = true;
+
+	ExecDeleteEpilogue(context, resultRelInfo, tupleid, oldtuple, changingPart);
+
+	/* Process RETURNING if present and if requested */
+	if (processReturning && resultRelInfo->ri_projectReturning)
+	{
+		/*
+		 * We have to put the target tuple into a slot, which means first we
+		 * gotta fetch it.  We can use the trigger tuple slot.
+		 */
+		TupleTableSlot *rslot;
+
+		if (resultRelInfo->ri_FdwRoutine)
+		{
+			/* FDW must have provided a slot containing the deleted row */
+			Assert(!TupIsNull(slot));
+		}
+		else
+		{
+			slot = ExecGetReturningSlot(estate, resultRelInfo);
+			if (oldtuple != NULL)
+			{
+				ExecForceStoreHeapTuple(oldtuple, slot, false);
+			}
+			else
+			{
+				if (!table_tuple_fetch_row_version(resultRelationDesc, tupleid,
+												   SnapshotAny, slot))
+					elog(ERROR, "failed to fetch deleted tuple for DELETE RETURNING");
+			}
+		}
+
+		rslot = ExecProcessReturning(resultRelInfo, slot, context->planSlot);
+
+		/*
+		 * Before releasing the target tuple again, make sure rslot has a
+		 * local copy of any pass-by-reference values.
+		 */
+		ExecMaterializeSlot(rslot);
+
+		ExecClearTuple(slot);
+
+		return rslot;
+	}
+
+	return NULL;
+}
+
+/*
+ * ExecCrossPartitionUpdate --- Move an updated tuple to another partition.
+ *
+ * This works by first deleting the old tuple from the current partition,
+ * followed by inserting the new tuple into the root parent table, that is,
+ * mtstate->rootResultRelInfo.  It will be re-routed from there to the
+ * correct partition.
+ *
+ * Returns true if the tuple has been successfully moved, or if it's found
+ * that the tuple was concurrently deleted so there's nothing more to do
+ * for the caller.
+ *
+ * False is returned if the tuple we're trying to move is found to have been
+ * concurrently updated.  In that case, the caller must check if the updated
+ * tuple that's returned in *retry_slot still needs to be re-routed, and call
+ * this function again or perform a regular update accordingly.  For MERGE,
+ * the updated tuple is not returned in *retry_slot; it has its own retry
+ * logic.
+ */
+static bool
+ExecCrossPartitionUpdate(ModifyTableContext *context,
+						 ResultRelInfo *resultRelInfo,
+						 ItemPointer tupleid, HeapTuple oldtuple,
+						 TupleTableSlot *slot,
+						 bool canSetTag,
+						 UpdateContext *updateCxt,
+						 TupleTableSlot **retry_slot,
+						 TupleTableSlot **inserted_tuple,
+						 ResultRelInfo **insert_destrel)
+{
+	ModifyTableState *mtstate = context->mtstate;
+	EState	   *estate = mtstate->ps.state;
+	TupleConversionMap *tupconv_map;
+	bool		tuple_deleted;
+	TupleTableSlot *epqslot = NULL;
+
+	context->cpUpdateReturningSlot = NULL;
+	*retry_slot = NULL;
+
+	/*
+	 * Disallow an INSERT ON CONFLICT DO UPDATE that causes the original row
+	 * to migrate to a different partition.  Maybe this can be implemented
+	 * some day, but it seems a fringe feature with little redeeming value.
+	 */
+	if (((ModifyTable *) mtstate->ps.plan)->onConflictAction == ONCONFLICT_UPDATE)
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("invalid ON UPDATE specification"),
+				 errdetail("The result tuple would appear in a different partition than the original tuple.")));
+
+	/*
+	 * When an UPDATE is run directly on a leaf partition, simply fail with a
+	 * partition constraint violation error.
+	 */
+	if (resultRelInfo == mtstate->rootResultRelInfo)
+		ExecPartitionCheckEmitError(resultRelInfo, slot, estate);
+
+	/* Initialize tuple routing info if not already done. */
+	if (mtstate->mt_partition_tuple_routing == NULL)
+	{
+		Relation	rootRel = mtstate->rootResultRelInfo->ri_RelationDesc;
+		MemoryContext oldcxt;
+
+		/* Things built here have to last for the query duration. */
+		oldcxt = MemoryContextSwitchTo(estate->es_query_cxt);
+
+		mtstate->mt_partition_tuple_routing =
+			ExecSetupPartitionTupleRouting(estate, rootRel);
+
+		/*
+		 * Before a partition's tuple can be re-routed, it must first be
+		 * converted to the root's format, so we'll need a slot for storing
+		 * such tuples.
+		 */
+		Assert(mtstate->mt_root_tuple_slot == NULL);
+		mtstate->mt_root_tuple_slot = table_slot_create(rootRel, NULL);
+
+		MemoryContextSwitchTo(oldcxt);
+	}
+
+	/*
+	 * Row movement, part 1.  Delete the tuple, but skip RETURNING processing.
+	 * We want to return rows from INSERT.
+	 */
+	ExecDelete(context, resultRelInfo,
+			   tupleid, oldtuple,
+			   false,			/* processReturning */
+			   true,			/* changingPart */
+			   false,			/* canSetTag */
+			   &tuple_deleted, &epqslot);
+
+	/*
+	 * For some reason if DELETE didn't happen (e.g. trigger prevented it, or
+	 * it was already deleted by self, or it was concurrently deleted by
+	 * another transaction), then we should skip the insert as well;
+	 * otherwise, an UPDATE could cause an increase in the total number of
+	 * rows across all partitions, which is clearly wrong.
+	 *
+	 * For a normal UPDATE, the case where the tuple has been the subject of a
+	 * concurrent UPDATE or DELETE would be handled by the EvalPlanQual
+	 * machinery, but for an UPDATE that we've translated into a DELETE from
+	 * this partition and an INSERT into some other partition, that's not
+	 * available, because CTID chains can't span relation boundaries.  We
+	 * mimic the semantics to a limited extent by skipping the INSERT if the
+	 * DELETE fails to find a tuple.  This ensures that two concurrent
+	 * attempts to UPDATE the same tuple at the same time can't turn one tuple
+	 * into two, and that an UPDATE of a just-deleted tuple can't resurrect
+	 * it.
+	 */
+	if (!tuple_deleted)
+	{
+		/*
+		 * epqslot will be typically NULL.  But when ExecDelete() finds that
+		 * another transaction has concurrently updated the same row, it
+		 * re-fetches the row, skips the delete, and epqslot is set to the
+		 * re-fetched tuple slot.  In that case, we need to do all the checks
+		 * again.  For MERGE, we leave everything to the caller (it must do
+		 * additional rechecking, and might end up executing a different
+		 * action entirely).
+		 */
+		if (context->relaction != NULL)
+			return false;
+		else if (TupIsNull(epqslot))
+			return true;
+		else
+		{
+			/* Fetch the most recent version of old tuple. */
+			TupleTableSlot *oldSlot;
+
+			/* ... but first, make sure ri_oldTupleSlot is initialized. */
+			if (unlikely(!resultRelInfo->ri_projectNewInfoValid))
+				ExecInitUpdateProjection(mtstate, resultRelInfo);
+			oldSlot = resultRelInfo->ri_oldTupleSlot;
+			if (!table_tuple_fetch_row_version(resultRelInfo->ri_RelationDesc,
+											   tupleid,
+											   SnapshotAny,
+											   oldSlot))
+				elog(ERROR, "failed to fetch tuple being updated");
+			/* and project the new tuple to retry the UPDATE with */
+			*retry_slot = ExecGetUpdateNewTuple(resultRelInfo, epqslot,
+												oldSlot);
+			return false;
+		}
+	}
+
+	/*
+	 * resultRelInfo is one of the per-relation resultRelInfos.  So we should
+	 * convert the tuple into root's tuple descriptor if needed, since
+	 * ExecInsert() starts the search from root.
+	 */
+	tupconv_map = ExecGetChildToRootMap(resultRelInfo);
+	if (tupconv_map != NULL)
+		slot = execute_attr_map_slot(tupconv_map->attrMap,
+									 slot,
+									 mtstate->mt_root_tuple_slot);
+
+	/* Tuple routing starts from the root table. */
+	context->cpUpdateReturningSlot =
+		ExecInsert(context, mtstate->rootResultRelInfo, slot, canSetTag,
+				   inserted_tuple, insert_destrel);
+
+	/*
+	 * Reset the transition state that may possibly have been written by
+	 * INSERT.
+	 */
+	if (mtstate->mt_transition_capture)
+		mtstate->mt_transition_capture->tcs_original_insert_tuple = NULL;
+
+	/* We're done moving. */
+	return true;
+}
+
+/*
+ * ExecUpdatePrologue -- subroutine for ExecUpdate
+ *
+ * Prepare executor state for UPDATE.  This includes running BEFORE ROW
+ * triggers.  We return false if one of them makes the update a no-op;
+ * otherwise, return true.
+ */
+static bool
+ExecUpdatePrologue(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
+				   ItemPointer tupleid, HeapTuple oldtuple, TupleTableSlot *slot,
+				   TM_Result *result)
+{
+	Relation	resultRelationDesc = resultRelInfo->ri_RelationDesc;
+
+	if (result)
+		*result = TM_Ok;
+
+	ExecMaterializeSlot(slot);
+
+	/*
+	 * Open the table's indexes, if we have not done so already, so that we
+	 * can add new index entries for the updated tuple.
+	 */
+	if (resultRelationDesc->rd_rel->relhasindex &&
+		resultRelInfo->ri_IndexRelationDescs == NULL)
+		ExecOpenIndices(resultRelInfo, false);
+
+	/* BEFORE ROW UPDATE triggers */
+	if (resultRelInfo->ri_TrigDesc &&
+		resultRelInfo->ri_TrigDesc->trig_update_before_row)
+	{
+		/* Flush any pending inserts, so rows are visible to the triggers */
+		if (context->estate->es_insert_pending_result_relations != NIL)
+			ExecPendingInserts(context->estate);
+
+		return ExecBRUpdateTriggersNew(context->estate, context->epqstate,
+									   resultRelInfo, tupleid, oldtuple, slot,
+									   result, &context->tmfd);
+	}
+
+	return true;
+}
+
+/*
+ * ExecUpdatePrepareSlot -- subroutine for ExecUpdateAct
+ *
+ * Apply the final modifications to the tuple slot before the update.
+ * (This is split out because we also need it in the foreign-table code path.)
+ */
+static void
+ExecUpdatePrepareSlot(ResultRelInfo *resultRelInfo,
+					  TupleTableSlot *slot,
+					  EState *estate)
+{
+	Relation	resultRelationDesc = resultRelInfo->ri_RelationDesc;
+
+	/*
+	 * Constraints and GENERATED expressions might reference the tableoid
+	 * column, so (re-)initialize tts_tableOid before evaluating them.
+	 */
+	slot->tts_tableOid = RelationGetRelid(resultRelationDesc);
+
+	/*
+	 * Compute stored generated columns
+	 */
+	if (resultRelationDesc->rd_att->constr &&
+		resultRelationDesc->rd_att->constr->has_generated_stored)
+		ExecComputeStoredGenerated(resultRelInfo, estate, slot,
+								   CMD_UPDATE);
+}
+
+/*
+ * ExecUpdateAct -- subroutine for ExecUpdate
+ *
+ * Actually update the tuple, when operating on a plain table.  If the
+ * table is a partition, and the command was called referencing an ancestor
+ * partitioned table, this routine migrates the resulting tuple to another
+ * partition.
+ *
+ * The caller is in charge of keeping indexes current as necessary.  The
+ * caller is also in charge of doing EvalPlanQual if the tuple is found to
+ * be concurrently updated.  However, in case of a cross-partition update,
+ * this routine does it.
+ *
+ * Caller is in charge of doing EvalPlanQual as necessary, and of keeping
+ * indexes current for the update.
+ */
+static TM_Result
+ExecUpdateAct(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
+			  ItemPointer tupleid, HeapTuple oldtuple, TupleTableSlot *slot,
+			  bool canSetTag, UpdateContext *updateCxt)
+{
+	EState	   *estate = context->estate;
+	Relation	resultRelationDesc = resultRelInfo->ri_RelationDesc;
+	bool		partition_constraint_failed;
+	TM_Result	result;
+
+	updateCxt->crossPartUpdate = false;
+
+	/*
+	 * If we move the tuple to a new partition, we loop back here to recompute
+	 * GENERATED values (which are allowed to be different across partitions)
+	 * and recheck any RLS policies and constraints.  We do not fire any
+	 * BEFORE triggers of the new partition, however.
+	 */
+lreplace:
+	/* Fill in GENERATEd columns */
+	ExecUpdatePrepareSlot(resultRelInfo, slot, estate);
+
+	/* ensure slot is independent, consider e.g. EPQ */
+	ExecMaterializeSlot(slot);
+
+	/*
+	 * If partition constraint fails, this row might get moved to another
+	 * partition, in which case we should check the RLS CHECK policy just
+	 * before inserting into the new partition, rather than doing it here.
+	 * This is because a trigger on that partition might again change the row.
+	 * So skip the WCO checks if the partition constraint fails.
+	 */
+	partition_constraint_failed =
+		resultRelationDesc->rd_rel->relispartition &&
+		!ExecPartitionCheck(resultRelInfo, slot, estate, false);
+
+	/* Check any RLS UPDATE WITH CHECK policies */
+	if (!partition_constraint_failed &&
+		resultRelInfo->ri_WithCheckOptions != NIL)
+	{
+		/*
+		 * ExecWithCheckOptions() will skip any WCOs which are not of the kind
+		 * we are looking for at this point.
+		 */
+		ExecWithCheckOptions(WCO_RLS_UPDATE_CHECK,
+							 resultRelInfo, slot, estate);
+	}
+
+	/*
+	 * If a partition check failed, try to move the row into the right
+	 * partition.
+	 */
+	if (partition_constraint_failed)
+	{
+		TupleTableSlot *inserted_tuple,
+				   *retry_slot;
+		ResultRelInfo *insert_destrel = NULL;
+
+		/*
+		 * ExecCrossPartitionUpdate will first DELETE the row from the
+		 * partition it's currently in and then insert it back into the root
+		 * table, which will re-route it to the correct partition.  However,
+		 * if the tuple has been concurrently updated, a retry is needed.
+		 */
+		if (ExecCrossPartitionUpdate(context, resultRelInfo,
+									 tupleid, oldtuple, slot,
+									 canSetTag, updateCxt,
+									 &retry_slot,
+									 &inserted_tuple,
+									 &insert_destrel))
+		{
+			/* success! */
+			updateCxt->updated = true;
+			updateCxt->crossPartUpdate = true;
+
+			/*
+			 * If the partitioned table being updated is referenced in foreign
+			 * keys, queue up trigger events to check that none of them were
+			 * violated.  No special treatment is needed in
+			 * non-cross-partition update situations, because the leaf
+			 * partition's AR update triggers will take care of that.  During
+			 * cross-partition updates implemented as delete on the source
+			 * partition followed by insert on the destination partition,
+			 * AR-UPDATE triggers of the root table (that is, the table
+			 * mentioned in the query) must be fired.
+			 *
+			 * NULL insert_destrel means that the move failed to occur, that
+			 * is, the update failed, so no need to anything in that case.
+			 */
+			if (insert_destrel &&
+				resultRelInfo->ri_TrigDesc &&
+				resultRelInfo->ri_TrigDesc->trig_update_after_row)
+				ExecCrossPartitionUpdateForeignKey(context,
+												   resultRelInfo,
+												   insert_destrel,
+												   tupleid, slot,
+												   inserted_tuple);
+
+			return TM_Ok;
+		}
+
+		/*
+		 * No luck, a retry is needed.  If running MERGE, we do not do so
+		 * here; instead let it handle that on its own rules.
+		 */
+		if (context->relaction != NULL)
+			return TM_Updated;
+
+		/*
+		 * ExecCrossPartitionUpdate installed an updated version of the new
+		 * tuple in the retry slot; start over.
+		 */
+		slot = retry_slot;
+		goto lreplace;
+	}
+
+	/*
+	 * Check the constraints of the tuple.  We've already checked the
+	 * partition constraint above; however, we must still ensure the tuple
+	 * passes all other constraints, so we will call ExecConstraints() and
+	 * have it validate all remaining checks.
+	 */
+	if (resultRelationDesc->rd_att->constr)
+		ExecConstraints(resultRelInfo, slot, estate);
+
+	/*
+	 * replace the heap tuple
+	 *
+	 * Note: if es_crosscheck_snapshot isn't InvalidSnapshot, we check that
+	 * the row to be updated is visible to that snapshot, and throw a
+	 * can't-serialize error if not. This is a special-case behavior needed
+	 * for referential integrity updates in transaction-snapshot mode
+	 * transactions.
+	 */
+	result = table_tuple_update(resultRelationDesc, tupleid, slot,
+								estate->es_output_cid,
+								estate->es_snapshot,
+								estate->es_crosscheck_snapshot,
+								true /* wait for commit */ ,
+								&context->tmfd, &updateCxt->lockmode,
+								&updateCxt->updateIndexes);
+	if (result == TM_Ok)
+		updateCxt->updated = true;
+
+	return result;
+}
+
+/*
+ * ExecUpdateEpilogue -- subroutine for ExecUpdate
+ *
+ * Closing steps of updating a tuple.  Must be called if ExecUpdateAct
+ * returns indicating that the tuple was updated.
+ */
+static void
+ExecUpdateEpilogue(ModifyTableContext *context, UpdateContext *updateCxt,
+				   ResultRelInfo *resultRelInfo, ItemPointer tupleid,
+				   HeapTuple oldtuple, TupleTableSlot *slot)
+{
+	ModifyTableState *mtstate = context->mtstate;
+	List	   *recheckIndexes = NIL;
+
+	/* insert index entries for tuple if necessary */
+	if (resultRelInfo->ri_NumIndices > 0 && updateCxt->updateIndexes)
+		recheckIndexes = ExecInsertIndexTuples(resultRelInfo,
+											   slot, context->estate,
+											   true, false,
+											   NULL, NIL);
+
+	/* AFTER ROW UPDATE Triggers */
+	ExecARUpdateTriggers(context->estate, resultRelInfo,
+						 NULL, NULL,
+						 tupleid, oldtuple, slot,
+						 recheckIndexes,
+						 mtstate->operation == CMD_INSERT ?
+						 mtstate->mt_oc_transition_capture :
+						 mtstate->mt_transition_capture,
+						 false);
+
+	list_free(recheckIndexes);
+
+	/*
+	 * Check any WITH CHECK OPTION constraints from parent views.  We are
+	 * required to do this after testing all constraints and uniqueness
+	 * violations per the SQL spec, so we do it after actually updating the
+	 * record in the heap and all indexes.
+	 *
+	 * ExecWithCheckOptions() will skip any WCOs which are not of the kind we
+	 * are looking for at this point.
+	 */
+	if (resultRelInfo->ri_WithCheckOptions != NIL)
+		ExecWithCheckOptions(WCO_VIEW_CHECK, resultRelInfo,
+							 slot, context->estate);
+}
+
+/*
+ * Queues up an update event using the target root partitioned table's
+ * trigger to check that a cross-partition update hasn't broken any foreign
+ * keys pointing into it.
+ */
+static void
+ExecCrossPartitionUpdateForeignKey(ModifyTableContext *context,
+								   ResultRelInfo *sourcePartInfo,
+								   ResultRelInfo *destPartInfo,
+								   ItemPointer tupleid,
+								   TupleTableSlot *oldslot,
+								   TupleTableSlot *newslot)
+{
+	ListCell   *lc;
+	ResultRelInfo *rootRelInfo;
+	List	   *ancestorRels;
+
+	rootRelInfo = sourcePartInfo->ri_RootResultRelInfo;
+	ancestorRels = ExecGetAncestorResultRels(context->estate, sourcePartInfo);
+
+	/*
+	 * For any foreign keys that point directly into a non-root ancestors of
+	 * the source partition, we can in theory fire an update event to enforce
+	 * those constraints using their triggers, if we could tell that both the
+	 * source and the destination partitions are under the same ancestor. But
+	 * for now, we simply report an error that those cannot be enforced.
+	 */
+	foreach(lc, ancestorRels)
+	{
+		ResultRelInfo *rInfo = lfirst(lc);
+		TriggerDesc *trigdesc = rInfo->ri_TrigDesc;
+		bool		has_noncloned_fkey = false;
+
+		/* Root ancestor's triggers will be processed. */
+		if (rInfo == rootRelInfo)
+			continue;
+
+		if (trigdesc && trigdesc->trig_update_after_row)
+		{
+			for (int i = 0; i < trigdesc->numtriggers; i++)
+			{
+				Trigger    *trig = &trigdesc->triggers[i];
+
+				if (!trig->tgisclone &&
+					RI_FKey_trigger_type(trig->tgfoid) == RI_TRIGGER_PK)
+				{
+					has_noncloned_fkey = true;
+					break;
+				}
+			}
+		}
+
+		if (has_noncloned_fkey)
+			ereport(ERROR,
+					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					 errmsg("cannot move tuple across partitions when a non-root ancestor of the source partition is directly referenced in a foreign key"),
+					 errdetail("A foreign key points to ancestor \"%s\" but not the root ancestor \"%s\".",
+							   RelationGetRelationName(rInfo->ri_RelationDesc),
+							   RelationGetRelationName(rootRelInfo->ri_RelationDesc)),
+					 errhint("Consider defining the foreign key on table \"%s\".",
+							 RelationGetRelationName(rootRelInfo->ri_RelationDesc))));
+	}
+
+	/* Perform the root table's triggers. */
+	ExecARUpdateTriggers(context->estate,
+						 rootRelInfo, sourcePartInfo, destPartInfo,
+						 tupleid, NULL, newslot, NIL, NULL, true);
+}
+
+/* ----------------------------------------------------------------
+ *		ExecUpdate
+ *
+ *		note: we can't run UPDATE queries with transactions
+ *		off because UPDATEs are actually INSERTs and our
+ *		scan will mistakenly loop forever, updating the tuple
+ *		it just inserted..  This should be fixed but until it
+ *		is, we don't want to get stuck in an infinite loop
+ *		which corrupts your database..
+ *
+ *		When updating a table, tupleid identifies the tuple to
+ *		update and oldtuple is NULL.  When updating a view, oldtuple
+ *		is passed to the INSTEAD OF triggers and identifies what to
+ *		update, and tupleid is invalid.  When updating a foreign table,
+ *		tupleid is invalid; the FDW has to figure out which row to
+ *		update using data from the planSlot.  oldtuple is passed to
+ *		foreign table triggers; it is NULL when the foreign table has
+ *		no relevant triggers.
+ *
+ *		slot contains the new tuple value to be stored.
+ *		planSlot is the output of the ModifyTable's subplan; we use it
+ *		to access values from other input tables (for RETURNING),
+ *		row-ID junk columns, etc.
+ *
+ *		Returns RETURNING result if any, otherwise NULL.
+ * ----------------------------------------------------------------
+ */
+static TupleTableSlot *
+ExecUpdate(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
+		   ItemPointer tupleid, HeapTuple oldtuple, TupleTableSlot *slot,
+		   bool canSetTag)
+{
+	EState	   *estate = context->estate;
+	Relation	resultRelationDesc = resultRelInfo->ri_RelationDesc;
+	UpdateContext updateCxt = {0};
+	TM_Result	result;
+
+	/*
+	 * abort the operation if not running transactions
+	 */
+	if (IsBootstrapProcessingMode())
+		elog(ERROR, "cannot UPDATE during bootstrap");
+
+	/*
+	 * Prepare for the update.  This includes BEFORE ROW triggers, so we're
+	 * done if it says we are.
+	 */
+	if (!ExecUpdatePrologue(context, resultRelInfo, tupleid, oldtuple, slot, NULL))
+		return NULL;
+
+	/* INSTEAD OF ROW UPDATE Triggers */
+	if (resultRelInfo->ri_TrigDesc &&
+		resultRelInfo->ri_TrigDesc->trig_update_instead_row)
+	{
+		if (!ExecIRUpdateTriggers(estate, resultRelInfo,
+								  oldtuple, slot))
+			return NULL;		/* "do nothing" */
+	}
+	else if (resultRelInfo->ri_FdwRoutine)
+	{
+		/* Fill in GENERATEd columns */
+		ExecUpdatePrepareSlot(resultRelInfo, slot, estate);
+
+		/*
+		 * update in foreign table: let the FDW do it
+		 */
+		slot = resultRelInfo->ri_FdwRoutine->ExecForeignUpdate(estate,
+															   resultRelInfo,
+															   slot,
+															   context->planSlot);
+
+		if (slot == NULL)		/* "do nothing" */
+			return NULL;
+
+		/*
+		 * AFTER ROW Triggers or RETURNING expressions might reference the
+		 * tableoid column, so (re-)initialize tts_tableOid before evaluating
+		 * them.  (This covers the case where the FDW replaced the slot.)
+		 */
+		slot->tts_tableOid = RelationGetRelid(resultRelationDesc);
+	}
+	else
+	{
+		/*
+		 * If we generate a new candidate tuple after EvalPlanQual testing, we
+		 * must loop back here to try again.  (We don't need to redo triggers,
+		 * however.  If there are any BEFORE triggers then trigger.c will have
+		 * done table_tuple_lock to lock the correct tuple, so there's no need
+		 * to do them again.)
+		 */
+redo_act:
+		result = ExecUpdateAct(context, resultRelInfo, tupleid, oldtuple, slot,
+							   canSetTag, &updateCxt);
+
+		/*
+		 * If ExecUpdateAct reports that a cross-partition update was done,
+		 * then the RETURNING tuple (if any) has been projected and there's
+		 * nothing else for us to do.
+		 */
+		if (updateCxt.crossPartUpdate)
+			return context->cpUpdateReturningSlot;
+
+		switch (result)
+		{
+			case TM_SelfModified:
+
+				/*
+				 * The target tuple was already updated or deleted by the
+				 * current command, or by a later command in the current
+				 * transaction.  The former case is possible in a join UPDATE
+				 * where multiple tuples join to the same target tuple. This
+				 * is pretty questionable, but Postgres has always allowed it:
+				 * we just execute the first update action and ignore
+				 * additional update attempts.
+				 *
+				 * The latter case arises if the tuple is modified by a
+				 * command in a BEFORE trigger, or perhaps by a command in a
+				 * volatile function used in the query.  In such situations we
+				 * should not ignore the update, but it is equally unsafe to
+				 * proceed.  We don't want to discard the original UPDATE
+				 * while keeping the triggered actions based on it; and we
+				 * have no principled way to merge this update with the
+				 * previous ones.  So throwing an error is the only safe
+				 * course.
+				 *
+				 * If a trigger actually intends this type of interaction, it
+				 * can re-execute the UPDATE (assuming it can figure out how)
+				 * and then return NULL to cancel the outer update.
+				 */
+				if (context->tmfd.cmax != estate->es_output_cid)
+					ereport(ERROR,
+							(errcode(ERRCODE_TRIGGERED_DATA_CHANGE_VIOLATION),
+							 errmsg("tuple to be updated was already modified by an operation triggered by the current command"),
+							 errhint("Consider using an AFTER trigger instead of a BEFORE trigger to propagate changes to other rows.")));
+
+				/* Else, already updated by self; nothing to do */
+				return NULL;
+
+			case TM_Ok:
+				break;
+
+			case TM_Updated:
+				{
+					TupleTableSlot *inputslot;
+					TupleTableSlot *epqslot;
+					TupleTableSlot *oldSlot;
+
+					if (IsolationUsesXactSnapshot())
+						ereport(ERROR,
+								(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+								 errmsg("could not serialize access due to concurrent update")));
+
+					/*
+					 * Already know that we're going to need to do EPQ, so
+					 * fetch tuple directly into the right slot.
+					 */
+					inputslot = EvalPlanQualSlot(context->epqstate, resultRelationDesc,
+												 resultRelInfo->ri_RangeTableIndex);
+
+					result = table_tuple_lock(resultRelationDesc, tupleid,
+											  estate->es_snapshot,
+											  inputslot, estate->es_output_cid,
+											  updateCxt.lockmode, LockWaitBlock,
+											  TUPLE_LOCK_FLAG_FIND_LAST_VERSION,
+											  &context->tmfd);
+
+					switch (result)
+					{
+						case TM_Ok:
+							Assert(context->tmfd.traversed);
+
+							epqslot = EvalPlanQual(context->epqstate,
+												   resultRelationDesc,
+												   resultRelInfo->ri_RangeTableIndex,
+												   inputslot);
+							if (TupIsNull(epqslot))
+								/* Tuple not passing quals anymore, exiting... */
+								return NULL;
+
+							/* Make sure ri_oldTupleSlot is initialized. */
+							if (unlikely(!resultRelInfo->ri_projectNewInfoValid))
+								ExecInitUpdateProjection(context->mtstate,
+														 resultRelInfo);
+
+							/* Fetch the most recent version of old tuple. */
+							oldSlot = resultRelInfo->ri_oldTupleSlot;
+							if (!table_tuple_fetch_row_version(resultRelationDesc,
+															   tupleid,
+															   SnapshotAny,
+															   oldSlot))
+								elog(ERROR, "failed to fetch tuple being updated");
+							slot = ExecGetUpdateNewTuple(resultRelInfo,
+														 epqslot, oldSlot);
+							goto redo_act;
+
+						case TM_Deleted:
+							/* tuple already deleted; nothing to do */
+							return NULL;
+
+						case TM_SelfModified:
+
+							/*
+							 * This can be reached when following an update
+							 * chain from a tuple updated by another session,
+							 * reaching a tuple that was already updated in
+							 * this transaction. If previously modified by
+							 * this command, ignore the redundant update,
+							 * otherwise error out.
+							 *
+							 * See also TM_SelfModified response to
+							 * table_tuple_update() above.
+							 */
+							if (context->tmfd.cmax != estate->es_output_cid)
+								ereport(ERROR,
+										(errcode(ERRCODE_TRIGGERED_DATA_CHANGE_VIOLATION),
+										 errmsg("tuple to be updated was already modified by an operation triggered by the current command"),
+										 errhint("Consider using an AFTER trigger instead of a BEFORE trigger to propagate changes to other rows.")));
+							return NULL;
+
+						default:
+							/* see table_tuple_lock call in ExecDelete() */
+							elog(ERROR, "unexpected table_tuple_lock status: %u",
+								 result);
+							return NULL;
+					}
+				}
+
+				break;
+
+			case TM_Deleted:
+				if (IsolationUsesXactSnapshot())
+					ereport(ERROR,
+							(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+							 errmsg("could not serialize access due to concurrent delete")));
+				/* tuple already deleted; nothing to do */
+				return NULL;
+
+			default:
+				elog(ERROR, "unrecognized table_tuple_update status: %u",
+					 result);
+				return NULL;
+		}
+	}
+
+	if (canSetTag)
+		(estate->es_processed)++;
+
+	ExecUpdateEpilogue(context, &updateCxt, resultRelInfo, tupleid, oldtuple,
+					   slot);
+
+	/* Process RETURNING if present */
+	if (resultRelInfo->ri_projectReturning)
+		return ExecProcessReturning(resultRelInfo, slot, context->planSlot);
+
+	return NULL;
+}
+
+/*
+ * ExecOnConflictUpdate --- execute UPDATE of INSERT ON CONFLICT DO UPDATE
+ *
+ * Try to lock tuple for update as part of speculative insertion.  If
+ * a qual originating from ON CONFLICT DO UPDATE is satisfied, update
+ * (but still lock row, even though it may not satisfy estate's
+ * snapshot).
+ *
+ * Returns true if we're done (with or without an update), or false if
+ * the caller must retry the INSERT from scratch.
+ */
+static bool
+ExecOnConflictUpdate(ModifyTableContext *context,
+					 ResultRelInfo *resultRelInfo,
+					 ItemPointer conflictTid,
+					 TupleTableSlot *excludedSlot,
+					 bool canSetTag,
+					 TupleTableSlot **returning)
+{
+	ModifyTableState *mtstate = context->mtstate;
+	ExprContext *econtext = mtstate->ps.ps_ExprContext;
+	Relation	relation = resultRelInfo->ri_RelationDesc;
+	ExprState  *onConflictSetWhere = resultRelInfo->ri_onConflict->oc_WhereClause;
+	TupleTableSlot *existing = resultRelInfo->ri_onConflict->oc_Existing;
+	TM_FailureData tmfd;
+	LockTupleMode lockmode;
+	TM_Result	test;
+	Datum		xminDatum;
+	TransactionId xmin;
+	bool		isnull;
+
+	/* Determine lock mode to use */
+	lockmode = ExecUpdateLockMode(context->estate, resultRelInfo);
+
+	/*
+	 * Lock tuple for update.  Don't follow updates when tuple cannot be
+	 * locked without doing so.  A row locking conflict here means our
+	 * previous conclusion that the tuple is conclusively committed is not
+	 * true anymore.
+	 */
+	test = table_tuple_lock(relation, conflictTid,
+							context->estate->es_snapshot,
+							existing, context->estate->es_output_cid,
+							lockmode, LockWaitBlock, 0,
+							&tmfd);
+	switch (test)
+	{
+		case TM_Ok:
+			/* success! */
+			break;
+
+		case TM_Invisible:
+
+			/*
+			 * This can occur when a just inserted tuple is updated again in
+			 * the same command. E.g. because multiple rows with the same
+			 * conflicting key values are inserted.
+			 *
+			 * This is somewhat similar to the ExecUpdate() TM_SelfModified
+			 * case.  We do not want to proceed because it would lead to the
+			 * same row being updated a second time in some unspecified order,
+			 * and in contrast to plain UPDATEs there's no historical behavior
+			 * to break.
+			 *
+			 * It is the user's responsibility to prevent this situation from
+			 * occurring.  These problems are why the SQL standard similarly
+			 * specifies that for SQL MERGE, an exception must be raised in
+			 * the event of an attempt to update the same row twice.
+			 */
+			xminDatum = slot_getsysattr(existing,
+										MinTransactionIdAttributeNumber,
+										&isnull);
+			Assert(!isnull);
+			xmin = DatumGetTransactionId(xminDatum);
+
+			if (TransactionIdIsCurrentTransactionId(xmin))
+				ereport(ERROR,
+						(errcode(ERRCODE_CARDINALITY_VIOLATION),
+				/* translator: %s is a SQL command name */
+						 errmsg("%s command cannot affect row a second time",
+								"ON CONFLICT DO UPDATE"),
+						 errhint("Ensure that no rows proposed for insertion within the same command have duplicate constrained values.")));
+
+			/* This shouldn't happen */
+			elog(ERROR, "attempted to lock invisible tuple");
+			break;
+
+		case TM_SelfModified:
+
+			/*
+			 * This state should never be reached. As a dirty snapshot is used
+			 * to find conflicting tuples, speculative insertion wouldn't have
+			 * seen this row to conflict with.
+			 */
+			elog(ERROR, "unexpected self-updated tuple");
+			break;
+
+		case TM_Updated:
+			if (IsolationUsesXactSnapshot())
+				ereport(ERROR,
+						(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+						 errmsg("could not serialize access due to concurrent update")));
+
+			/*
+			 * As long as we don't support an UPDATE of INSERT ON CONFLICT for
+			 * a partitioned table we shouldn't reach to a case where tuple to
+			 * be lock is moved to another partition due to concurrent update
+			 * of the partition key.
+			 */
+			Assert(!ItemPointerIndicatesMovedPartitions(&tmfd.ctid));
+
+			/*
+			 * Tell caller to try again from the very start.
+			 *
+			 * It does not make sense to use the usual EvalPlanQual() style
+			 * loop here, as the new version of the row might not conflict
+			 * anymore, or the conflicting tuple has actually been deleted.
+			 */
+			ExecClearTuple(existing);
+			return false;
+
+		case TM_Deleted:
+			if (IsolationUsesXactSnapshot())
+				ereport(ERROR,
+						(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+						 errmsg("could not serialize access due to concurrent delete")));
+
+			/* see TM_Updated case */
+			Assert(!ItemPointerIndicatesMovedPartitions(&tmfd.ctid));
+			ExecClearTuple(existing);
+			return false;
+
+		default:
+			elog(ERROR, "unrecognized table_tuple_lock status: %u", test);
+	}
+
+	/* Success, the tuple is locked. */
+
+	/*
+	 * Verify that the tuple is visible to our MVCC snapshot if the current
+	 * isolation level mandates that.
+	 *
+	 * It's not sufficient to rely on the check within ExecUpdate() as e.g.
+	 * CONFLICT ... WHERE clause may prevent us from reaching that.
+	 *
+	 * This means we only ever continue when a new command in the current
+	 * transaction could see the row, even though in READ COMMITTED mode the
+	 * tuple will not be visible according to the current statement's
+	 * snapshot.  This is in line with the way UPDATE deals with newer tuple
+	 * versions.
+	 */
+	ExecCheckTupleVisible(context->estate, relation, existing);
+
+	/*
+	 * Make tuple and any needed join variables available to ExecQual and
+	 * ExecProject.  The EXCLUDED tuple is installed in ecxt_innertuple, while
+	 * the target's existing tuple is installed in the scantuple.  EXCLUDED
+	 * has been made to reference INNER_VAR in setrefs.c, but there is no
+	 * other redirection.
+	 */
+	econtext->ecxt_scantuple = existing;
+	econtext->ecxt_innertuple = excludedSlot;
+	econtext->ecxt_outertuple = NULL;
+
+	if (!ExecQual(onConflictSetWhere, econtext))
+	{
+		ExecClearTuple(existing);	/* see return below */
+		InstrCountFiltered1(&mtstate->ps, 1);
+		return true;			/* done with the tuple */
+	}
+
+	if (resultRelInfo->ri_WithCheckOptions != NIL)
+	{
+		/*
+		 * Check target's existing tuple against UPDATE-applicable USING
+		 * security barrier quals (if any), enforced here as RLS checks/WCOs.
+		 *
+		 * The rewriter creates UPDATE RLS checks/WCOs for UPDATE security
+		 * quals, and stores them as WCOs of "kind" WCO_RLS_CONFLICT_CHECK,
+		 * but that's almost the extent of its special handling for ON
+		 * CONFLICT DO UPDATE.
+		 *
+		 * The rewriter will also have associated UPDATE applicable straight
+		 * RLS checks/WCOs for the benefit of the ExecUpdate() call that
+		 * follows.  INSERTs and UPDATEs naturally have mutually exclusive WCO
+		 * kinds, so there is no danger of spurious over-enforcement in the
+		 * INSERT or UPDATE path.
+		 */
+		ExecWithCheckOptions(WCO_RLS_CONFLICT_CHECK, resultRelInfo,
+							 existing,
+							 mtstate->ps.state);
+	}
+
+	/* Project the new tuple version */
+	ExecProject(resultRelInfo->ri_onConflict->oc_ProjInfo);
+
+	/*
+	 * Note that it is possible that the target tuple has been modified in
+	 * this session, after the above table_tuple_lock. We choose to not error
+	 * out in that case, in line with ExecUpdate's treatment of similar cases.
+	 * This can happen if an UPDATE is triggered from within ExecQual(),
+	 * ExecWithCheckOptions() or ExecProject() above, e.g. by selecting from a
+	 * wCTE in the ON CONFLICT's SET.
+	 */
+
+	/* Execute UPDATE with projection */
+	*returning = ExecUpdate(context, resultRelInfo,
+							conflictTid, NULL,
+							resultRelInfo->ri_onConflict->oc_ProjSlot,
+							canSetTag);
+
+	/*
+	 * Clear out existing tuple, as there might not be another conflict among
+	 * the next input rows. Don't want to hold resources till the end of the
+	 * query.
+	 */
+	ExecClearTuple(existing);
+	return true;
+}
+
+/*
+ * Perform MERGE.
+ */
+static TupleTableSlot *
+ExecMerge(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
+		  ItemPointer tupleid, bool canSetTag)
+{
+	bool		matched;
+
+	/*-----
+	 * If we are dealing with a WHEN MATCHED case (tupleid is valid), we
+	 * execute the first action for which the additional WHEN MATCHED AND
+	 * quals pass.  If an action without quals is found, that action is
+	 * executed.
+	 *
+	 * Similarly, if we are dealing with WHEN NOT MATCHED case, we look at
+	 * the given WHEN NOT MATCHED actions in sequence until one passes.
+	 *
+	 * Things get interesting in case of concurrent update/delete of the
+	 * target tuple. Such concurrent update/delete is detected while we are
+	 * executing a WHEN MATCHED action.
+	 *
+	 * A concurrent update can:
+	 *
+	 * 1. modify the target tuple so that it no longer satisfies the
+	 *    additional quals attached to the current WHEN MATCHED action
+	 *
+	 *    In this case, we are still dealing with a WHEN MATCHED case.
+	 *    We recheck the list of WHEN MATCHED actions from the start and
+	 *    choose the first one that satisfies the new target tuple.
+	 *
+	 * 2. modify the target tuple so that the join quals no longer pass and
+	 *    hence the source tuple no longer has a match.
+	 *
+	 *    In this case, the source tuple no longer matches the target tuple,
+	 *    so we now instead find a qualifying WHEN NOT MATCHED action to
+	 *    execute.
+	 *
+	 * XXX Hmmm, what if the updated tuple would now match one that was
+	 * considered NOT MATCHED so far?
+	 *
+	 * A concurrent delete changes a WHEN MATCHED case to WHEN NOT MATCHED.
+	 *
+	 * ExecMergeMatched takes care of following the update chain and
+	 * re-finding the qualifying WHEN MATCHED action, as long as the updated
+	 * target tuple still satisfies the join quals, i.e., it remains a WHEN
+	 * MATCHED case. If the tuple gets deleted or the join quals fail, it
+	 * returns and we try ExecMergeNotMatched. Given that ExecMergeMatched
+	 * always make progress by following the update chain and we never switch
+	 * from ExecMergeNotMatched to ExecMergeMatched, there is no risk of a
+	 * livelock.
+	 */
+	matched = tupleid != NULL;
+	if (matched)
+		matched = ExecMergeMatched(context, resultRelInfo, tupleid, canSetTag);
+
+	/*
+	 * Either we were dealing with a NOT MATCHED tuple or ExecMergeMatched()
+	 * returned "false", indicating the previously MATCHED tuple no longer
+	 * matches.
+	 */
+	if (!matched)
+		ExecMergeNotMatched(context, resultRelInfo, canSetTag);
+
+	/* No RETURNING support yet */
+	return NULL;
+}
+
+/*
+ * Check and execute the first qualifying MATCHED action. The current target
+ * tuple is identified by tupleid.
+ *
+ * We start from the first WHEN MATCHED action and check if the WHEN quals
+ * pass, if any. If the WHEN quals for the first action do not pass, we
+ * check the second, then the third and so on. If we reach to the end, no
+ * action is taken and we return true, indicating that no further action is
+ * required for this tuple.
+ *
+ * If we do find a qualifying action, then we attempt to execute the action.
+ *
+ * If the tuple is concurrently updated, EvalPlanQual is run with the updated
+ * tuple to recheck the join quals. Note that the additional quals associated
+ * with individual actions are evaluated by this routine via ExecQual, while
+ * EvalPlanQual checks for the join quals. If EvalPlanQual tells us that the
+ * updated tuple still passes the join quals, then we restart from the first
+ * action to look for a qualifying action. Otherwise, we return false --
+ * meaning that a NOT MATCHED action must now be executed for the current
+ * source tuple.
+ */
+static bool
+ExecMergeMatched(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
+				 ItemPointer tupleid, bool canSetTag)
+{
+	ModifyTableState *mtstate = context->mtstate;
+	TupleTableSlot *newslot;
+	EState	   *estate = context->estate;
+	ExprContext *econtext = mtstate->ps.ps_ExprContext;
+	bool		isNull;
+	EPQState   *epqstate = &mtstate->mt_epqstate;
+	ListCell   *l;
+
+	/*
+	 * If there are no WHEN MATCHED actions, we are done.
+	 */
+	if (resultRelInfo->ri_matchedMergeAction == NIL)
+		return true;
+
+	/*
+	 * Make tuple and any needed join variables available to ExecQual and
+	 * ExecProject. The target's existing tuple is installed in the scantuple.
+	 * Again, this target relation's slot is required only in the case of a
+	 * MATCHED tuple and UPDATE/DELETE actions.
+	 */
+	econtext->ecxt_scantuple = resultRelInfo->ri_oldTupleSlot;
+	econtext->ecxt_innertuple = context->planSlot;
+	econtext->ecxt_outertuple = NULL;
+
+lmerge_matched:;
+
+	/*
+	 * This routine is only invoked for matched rows, and we must have found
+	 * the tupleid of the target row in that case; fetch that tuple.
+	 *
+	 * We use SnapshotAny for this because we might get called again after
+	 * EvalPlanQual returns us a new tuple, which may not be visible to our
+	 * MVCC snapshot.
+	 */
+
+	if (!table_tuple_fetch_row_version(resultRelInfo->ri_RelationDesc,
+									   tupleid,
+									   SnapshotAny,
+									   resultRelInfo->ri_oldTupleSlot))
+		elog(ERROR, "failed to fetch the target tuple");
+
+	foreach(l, resultRelInfo->ri_matchedMergeAction)
+	{
+		MergeActionState *relaction = (MergeActionState *) lfirst(l);
+		CmdType		commandType = relaction->mas_action->commandType;
+		TM_Result	result;
+		UpdateContext updateCxt = {0};
+
+		/*
+		 * Test condition, if any.
+		 *
+		 * In the absence of any condition, we perform the action
+		 * unconditionally (no need to check separately since ExecQual() will
+		 * return true if there are no conditions to evaluate).
+		 */
+		if (!ExecQual(relaction->mas_whenqual, econtext))
+			continue;
+
+		/*
+		 * Check if the existing target tuple meets the USING checks of
+		 * UPDATE/DELETE RLS policies. If those checks fail, we throw an
+		 * error.
+		 *
+		 * The WITH CHECK quals for UPDATE RLS policies are applied in
+		 * ExecUpdateAct() and hence we need not do anything special to handle
+		 * them.
+		 *
+		 * NOTE: We must do this after WHEN quals are evaluated, so that we
+		 * check policies only when they matter.
+		 */
+		if (resultRelInfo->ri_WithCheckOptions && commandType != CMD_NOTHING)
+		{
+			ExecWithCheckOptions(commandType == CMD_UPDATE ?
+								 WCO_RLS_MERGE_UPDATE_CHECK : WCO_RLS_MERGE_DELETE_CHECK,
+								 resultRelInfo,
+								 resultRelInfo->ri_oldTupleSlot,
+								 context->mtstate->ps.state);
+		}
+
+		/* Perform stated action */
+		switch (commandType)
+		{
+			case CMD_UPDATE:
+
+				/*
+				 * Project the output tuple, and use that to update the table.
+				 * We don't need to filter out junk attributes, because the
+				 * UPDATE action's targetlist doesn't have any.
+				 */
+				newslot = ExecProject(relaction->mas_proj);
+
+				context->relaction = relaction;
+				if (!ExecUpdatePrologue(context, resultRelInfo,
+										tupleid, NULL, newslot, &result))
+				{
+					if (result == TM_Ok)
+						return true;	/* "do nothing" */
+					break;		/* concurrent update/delete */
+				}
+				result = ExecUpdateAct(context, resultRelInfo, tupleid, NULL,
+									   newslot, false, &updateCxt);
+				if (result == TM_Ok && updateCxt.updated)
+				{
+					ExecUpdateEpilogue(context, &updateCxt, resultRelInfo,
+									   tupleid, NULL, newslot);
+					mtstate->mt_merge_updated += 1;
+				}
+				break;
+
+			case CMD_DELETE:
+				context->relaction = relaction;
+				if (!ExecDeletePrologue(context, resultRelInfo, tupleid,
+										NULL, NULL, &result))
+				{
+					if (result == TM_Ok)
+						return true;	/* "do nothing" */
+					break;		/* concurrent update/delete */
+				}
+				result = ExecDeleteAct(context, resultRelInfo, tupleid, false);
+				if (result == TM_Ok)
+				{
+					ExecDeleteEpilogue(context, resultRelInfo, tupleid, NULL,
+									   false);
+					mtstate->mt_merge_deleted += 1;
+				}
+				break;
+
+			case CMD_NOTHING:
+				/* Doing nothing is always OK */
+				result = TM_Ok;
+				break;
+
+			default:
+				elog(ERROR, "unknown action in MERGE WHEN MATCHED clause");
+		}
+
+		switch (result)
+		{
+			case TM_Ok:
+				/* all good; perform final actions */
+				if (canSetTag && commandType != CMD_NOTHING)
+					(estate->es_processed)++;
+
+				break;
+
+			case TM_SelfModified:
+
+				/*
+				 * The SQL standard disallows this for MERGE.
+				 */
+				if (TransactionIdIsCurrentTransactionId(context->tmfd.xmax))
+					ereport(ERROR,
+							(errcode(ERRCODE_CARDINALITY_VIOLATION),
+					/* translator: %s is a SQL command name */
+							 errmsg("%s command cannot affect row a second time",
+									"MERGE"),
+							 errhint("Ensure that not more than one source row matches any one target row.")));
+				/* This shouldn't happen */
+				elog(ERROR, "attempted to update or delete invisible tuple");
+				break;
+
+			case TM_Deleted:
+				if (IsolationUsesXactSnapshot())
+					ereport(ERROR,
+							(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+							 errmsg("could not serialize access due to concurrent delete")));
+
+				/*
+				 * If the tuple was already deleted, return to let caller
+				 * handle it under NOT MATCHED clauses.
+				 */
+				return false;
+
+			case TM_Updated:
+				{
+					Relation	resultRelationDesc;
+					TupleTableSlot *epqslot,
+							   *inputslot;
+					LockTupleMode lockmode;
+
+					/*
+					 * The target tuple was concurrently updated by some other
+					 * transaction. Run EvalPlanQual() with the new version of
+					 * the tuple. If it does not return a tuple, then we
+					 * switch to the NOT MATCHED list of actions. If it does
+					 * return a tuple and the join qual is still satisfied,
+					 * then we just need to recheck the MATCHED actions,
+					 * starting from the top, and execute the first qualifying
+					 * action.
+					 */
+					resultRelationDesc = resultRelInfo->ri_RelationDesc;
+					lockmode = ExecUpdateLockMode(estate, resultRelInfo);
+
+					inputslot = EvalPlanQualSlot(epqstate, resultRelationDesc,
+												 resultRelInfo->ri_RangeTableIndex);
+
+					result = table_tuple_lock(resultRelationDesc, tupleid,
+											  estate->es_snapshot,
+											  inputslot, estate->es_output_cid,
+											  lockmode, LockWaitBlock,
+											  TUPLE_LOCK_FLAG_FIND_LAST_VERSION,
+											  &context->tmfd);
+					switch (result)
+					{
+						case TM_Ok:
+							epqslot = EvalPlanQual(epqstate,
+												   resultRelationDesc,
+												   resultRelInfo->ri_RangeTableIndex,
+												   inputslot);
+
+							/*
+							 * If we got no tuple, or the tuple we get has a
+							 * NULL ctid, go back to caller: this one is not a
+							 * MATCHED tuple anymore, so they can retry with
+							 * NOT MATCHED actions.
+							 */
+							if (TupIsNull(epqslot))
+								return false;
+
+							(void) ExecGetJunkAttribute(epqslot,
+														resultRelInfo->ri_RowIdAttNo,
+														&isNull);
+							if (isNull)
+								return false;
+
+							/*
+							 * When a tuple was updated and migrated to
+							 * another partition concurrently, the current
+							 * MERGE implementation can't follow.  There's
+							 * probably a better way to handle this case, but
+							 * it'd require recognizing the relation to which
+							 * the tuple moved, and setting our current
+							 * resultRelInfo to that.
+							 */
+							if (ItemPointerIndicatesMovedPartitions(&context->tmfd.ctid))
+								ereport(ERROR,
+										(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+										 errmsg("tuple to be deleted was already moved to another partition due to concurrent update")));
+
+							/*
+							 * A non-NULL ctid means that we are still dealing
+							 * with MATCHED case. Restart the loop so that we
+							 * apply all the MATCHED rules again, to ensure
+							 * that the first qualifying WHEN MATCHED action
+							 * is executed.
+							 *
+							 * Update tupleid to that of the new tuple, for
+							 * the refetch we do at the top.
+							 */
+							ItemPointerCopy(&context->tmfd.ctid, tupleid);
+							goto lmerge_matched;
+
+						case TM_Deleted:
+
+							/*
+							 * tuple already deleted; tell caller to run NOT
+							 * MATCHED actions
+							 */
+							return false;
+
+						case TM_SelfModified:
+
+							/*
+							 * This can be reached when following an update
+							 * chain from a tuple updated by another session,
+							 * reaching a tuple that was already updated in
+							 * this transaction. If previously modified by
+							 * this command, ignore the redundant update,
+							 * otherwise error out.
+							 *
+							 * See also response to TM_SelfModified in
+							 * ExecUpdate().
+							 */
+							if (context->tmfd.cmax != estate->es_output_cid)
+								ereport(ERROR,
+										(errcode(ERRCODE_TRIGGERED_DATA_CHANGE_VIOLATION),
+										 errmsg("tuple to be updated or deleted was already modified by an operation triggered by the current command"),
+										 errhint("Consider using an AFTER trigger instead of a BEFORE trigger to propagate changes to other rows.")));
+							return false;
+
+						default:
+							/* see table_tuple_lock call in ExecDelete() */
+							elog(ERROR, "unexpected table_tuple_lock status: %u",
+								 result);
+							return false;
+					}
+				}
+
+			case TM_Invisible:
+			case TM_WouldBlock:
+			case TM_BeingModified:
+				/* these should not occur */
+				elog(ERROR, "unexpected tuple operation result: %d", result);
+				break;
+		}
+
+		/*
+		 * We've activated one of the WHEN clauses, so we don't search
+		 * further. This is required behaviour, not an optimization.
+		 */
+		break;
+	}
+
+	/*
+	 * Successfully executed an action or no qualifying action was found.
+	 */
+	return true;
+}
+
+/*
+ * Execute the first qualifying NOT MATCHED action.
+ */
+static void
+ExecMergeNotMatched(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
+					bool canSetTag)
+{
+	ModifyTableState *mtstate = context->mtstate;
+	ExprContext *econtext = mtstate->ps.ps_ExprContext;
+	List	   *actionStates = NIL;
+	ListCell   *l;
+
+	/*
+	 * For INSERT actions, the root relation's merge action is OK since the
+	 * INSERT's targetlist and the WHEN conditions can only refer to the
+	 * source relation and hence it does not matter which result relation we
+	 * work with.
+	 *
+	 * XXX does this mean that we can avoid creating copies of actionStates on
+	 * partitioned tables, for not-matched actions?
+	 */
+	actionStates = resultRelInfo->ri_notMatchedMergeAction;
+
+	/*
+	 * Make source tuple available to ExecQual and ExecProject. We don't need
+	 * the target tuple, since the WHEN quals and targetlist can't refer to
+	 * the target columns.
+	 */
+	econtext->ecxt_scantuple = NULL;
+	econtext->ecxt_innertuple = context->planSlot;
+	econtext->ecxt_outertuple = NULL;
+
+	foreach(l, actionStates)
+	{
+		MergeActionState *action = (MergeActionState *) lfirst(l);
+		CmdType		commandType = action->mas_action->commandType;
+		TupleTableSlot *newslot;
+
+		/*
+		 * Test condition, if any.
+		 *
+		 * In the absence of any condition, we perform the action
+		 * unconditionally (no need to check separately since ExecQual() will
+		 * return true if there are no conditions to evaluate).
+		 */
+		if (!ExecQual(action->mas_whenqual, econtext))
+			continue;
+
+		/* Perform stated action */
+		switch (commandType)
+		{
+			case CMD_INSERT:
+
+				/*
+				 * Project the tuple.  In case of a partitioned table, the
+				 * projection was already built to use the root's descriptor,
+				 * so we don't need to map the tuple here.
+				 */
+				newslot = ExecProject(action->mas_proj);
+				context->relaction = action;
+
+				(void) ExecInsert(context, mtstate->rootResultRelInfo, newslot,
+								  canSetTag, NULL, NULL);
+				mtstate->mt_merge_inserted += 1;
+				break;
+			case CMD_NOTHING:
+				/* Do nothing */
+				break;
+			default:
+				elog(ERROR, "unknown action in MERGE WHEN NOT MATCHED clause");
+		}
+
+		/*
+		 * We've activated one of the WHEN clauses, so we don't search
+		 * further. This is required behaviour, not an optimization.
+		 */
+		break;
+	}
+}
+
+/*
+ * Initialize state for execution of MERGE.
+ */
+void
+ExecInitMerge(ModifyTableState *mtstate, EState *estate)
+{
+	ModifyTable *node = (ModifyTable *) mtstate->ps.plan;
+	ResultRelInfo *rootRelInfo = mtstate->rootResultRelInfo;
+	ResultRelInfo *resultRelInfo;
+	ExprContext *econtext;
+	ListCell   *lc;
+	int			i;
+
+	if (node->mergeActionLists == NIL)
+		return;
+
+	mtstate->mt_merge_subcommands = 0;
+
+	if (mtstate->ps.ps_ExprContext == NULL)
+		ExecAssignExprContext(estate, &mtstate->ps);
+	econtext = mtstate->ps.ps_ExprContext;
+
+	/*
+	 * Create a MergeActionState for each action on the mergeActionList and
+	 * add it to either a list of matched actions or not-matched actions.
+	 *
+	 * Similar logic appears in ExecInitPartitionInfo(), so if changing
+	 * anything here, do so there too.
+	 */
+	i = 0;
+	foreach(lc, node->mergeActionLists)
+	{
+		List	   *mergeActionList = lfirst(lc);
+		TupleDesc	relationDesc;
+		ListCell   *l;
+
+		resultRelInfo = mtstate->resultRelInfo + i;
+		i++;
+		relationDesc = RelationGetDescr(resultRelInfo->ri_RelationDesc);
+
+		/* initialize slots for MERGE fetches from this rel */
+		if (unlikely(!resultRelInfo->ri_projectNewInfoValid))
+			ExecInitMergeTupleSlots(mtstate, resultRelInfo);
+
+		foreach(l, mergeActionList)
+		{
+			MergeAction *action = (MergeAction *) lfirst(l);
+			MergeActionState *action_state;
+			TupleTableSlot *tgtslot;
+			TupleDesc	tgtdesc;
+			List	  **list;
+
+			/*
+			 * Build action merge state for this rel.  (For partitions,
+			 * equivalent code exists in ExecInitPartitionInfo.)
+			 */
+			action_state = makeNode(MergeActionState);
+			action_state->mas_action = action;
+			action_state->mas_whenqual = ExecInitQual((List *) action->qual,
+													  &mtstate->ps);
+
+			/*
+			 * We create two lists - one for WHEN MATCHED actions and one for
+			 * WHEN NOT MATCHED actions - and stick the MergeActionState into
+			 * the appropriate list.
+			 */
+			if (action_state->mas_action->matched)
+				list = &resultRelInfo->ri_matchedMergeAction;
+			else
+				list = &resultRelInfo->ri_notMatchedMergeAction;
+			*list = lappend(*list, action_state);
+
+			switch (action->commandType)
+			{
+				case CMD_INSERT:
+					ExecCheckPlanOutput(rootRelInfo->ri_RelationDesc,
+										action->targetList);
+
+					/*
+					 * If the MERGE targets a partitioned table, any INSERT
+					 * actions must be routed through it, not the child
+					 * relations. Initialize the routing struct and the root
+					 * table's "new" tuple slot for that, if not already done.
+					 * The projection we prepare, for all relations, uses the
+					 * root relation descriptor, and targets the plan's root
+					 * slot.  (This is consistent with the fact that we
+					 * checked the plan output to match the root relation,
+					 * above.)
+					 */
+					if (rootRelInfo->ri_RelationDesc->rd_rel->relkind ==
+						RELKIND_PARTITIONED_TABLE)
+					{
+						if (mtstate->mt_partition_tuple_routing == NULL)
+						{
+							/*
+							 * Initialize planstate for routing if not already
+							 * done.
+							 *
+							 * Note that the slot is managed as a standalone
+							 * slot belonging to ModifyTableState, so we pass
+							 * NULL for the 2nd argument.
+							 */
+							mtstate->mt_root_tuple_slot =
+								table_slot_create(rootRelInfo->ri_RelationDesc,
+												  NULL);
+							mtstate->mt_partition_tuple_routing =
+								ExecSetupPartitionTupleRouting(estate,
+															   rootRelInfo->ri_RelationDesc);
+						}
+						tgtslot = mtstate->mt_root_tuple_slot;
+						tgtdesc = RelationGetDescr(rootRelInfo->ri_RelationDesc);
+					}
+					else
+					{
+						/* not partitioned? use the stock relation and slot */
+						tgtslot = resultRelInfo->ri_newTupleSlot;
+						tgtdesc = RelationGetDescr(resultRelInfo->ri_RelationDesc);
+					}
+
+					action_state->mas_proj =
+						ExecBuildProjectionInfo(action->targetList, econtext,
+												tgtslot,
+												&mtstate->ps,
+												tgtdesc);
+
+					mtstate->mt_merge_subcommands |= MERGE_INSERT;
+					break;
+				case CMD_UPDATE:
+					action_state->mas_proj =
+						ExecBuildUpdateProjection(action->targetList,
+												  true,
+												  action->updateColnos,
+												  relationDesc,
+												  econtext,
+												  resultRelInfo->ri_newTupleSlot,
+												  &mtstate->ps);
+					mtstate->mt_merge_subcommands |= MERGE_UPDATE;
+					break;
+				case CMD_DELETE:
+					mtstate->mt_merge_subcommands |= MERGE_DELETE;
+					break;
+				case CMD_NOTHING:
+					break;
+				default:
+					elog(ERROR, "unknown operation");
+					break;
+			}
+		}
+	}
+}
+
+/*
+ * Initializes the tuple slots in a ResultRelInfo for any MERGE action.
+ *
+ * We mark 'projectNewInfoValid' even though the projections themselves
+ * are not initialized here.
+ */
+void
+ExecInitMergeTupleSlots(ModifyTableState *mtstate,
+						ResultRelInfo *resultRelInfo)
+{
+	EState	   *estate = mtstate->ps.state;
+
+	Assert(!resultRelInfo->ri_projectNewInfoValid);
+
+	resultRelInfo->ri_oldTupleSlot =
+		table_slot_create(resultRelInfo->ri_RelationDesc,
+						  &estate->es_tupleTable);
+	resultRelInfo->ri_newTupleSlot =
+		table_slot_create(resultRelInfo->ri_RelationDesc,
+						  &estate->es_tupleTable);
+	resultRelInfo->ri_projectNewInfoValid = true;
+}
+
+/*
+ * Process BEFORE EACH STATEMENT triggers
+ */
+static void
+fireBSTriggers(ModifyTableState *node)
+{
+	ModifyTable *plan = (ModifyTable *) node->ps.plan;
+	ResultRelInfo *resultRelInfo = node->rootResultRelInfo;
+
+	switch (node->operation)
+	{
+		case CMD_INSERT:
+			ExecBSInsertTriggers(node->ps.state, resultRelInfo);
+			if (plan->onConflictAction == ONCONFLICT_UPDATE)
+				ExecBSUpdateTriggers(node->ps.state,
+									 resultRelInfo);
+			break;
+		case CMD_UPDATE:
+			ExecBSUpdateTriggers(node->ps.state, resultRelInfo);
+			break;
+		case CMD_DELETE:
+			ExecBSDeleteTriggers(node->ps.state, resultRelInfo);
+			break;
+		case CMD_MERGE:
+			if (node->mt_merge_subcommands & MERGE_INSERT)
+				ExecBSInsertTriggers(node->ps.state, resultRelInfo);
+			if (node->mt_merge_subcommands & MERGE_UPDATE)
+				ExecBSUpdateTriggers(node->ps.state, resultRelInfo);
+			if (node->mt_merge_subcommands & MERGE_DELETE)
+				ExecBSDeleteTriggers(node->ps.state, resultRelInfo);
+			break;
+		default:
+			elog(ERROR, "unknown operation");
+			break;
+	}
+}
+
+/*
+ * Process AFTER EACH STATEMENT triggers
+ */
+static void
+fireASTriggers(ModifyTableState *node)
+{
+	ModifyTable *plan = (ModifyTable *) node->ps.plan;
+	ResultRelInfo *resultRelInfo = node->rootResultRelInfo;
+
+	switch (node->operation)
+	{
+		case CMD_INSERT:
+			if (plan->onConflictAction == ONCONFLICT_UPDATE)
+				ExecASUpdateTriggers(node->ps.state,
+									 resultRelInfo,
+									 node->mt_oc_transition_capture);
+			ExecASInsertTriggers(node->ps.state, resultRelInfo,
+								 node->mt_transition_capture);
+			break;
+		case CMD_UPDATE:
+			ExecASUpdateTriggers(node->ps.state, resultRelInfo,
+								 node->mt_transition_capture);
+			break;
+		case CMD_DELETE:
+			ExecASDeleteTriggers(node->ps.state, resultRelInfo,
+								 node->mt_transition_capture);
+			break;
+		case CMD_MERGE:
+			if (node->mt_merge_subcommands & MERGE_DELETE)
+				ExecASDeleteTriggers(node->ps.state, resultRelInfo,
+									 node->mt_transition_capture);
+			if (node->mt_merge_subcommands & MERGE_UPDATE)
+				ExecASUpdateTriggers(node->ps.state, resultRelInfo,
+									 node->mt_transition_capture);
+			if (node->mt_merge_subcommands & MERGE_INSERT)
+				ExecASInsertTriggers(node->ps.state, resultRelInfo,
+									 node->mt_transition_capture);
+			break;
+		default:
+			elog(ERROR, "unknown operation");
+			break;
+	}
+}
+
+/*
+ * Set up the state needed for collecting transition tuples for AFTER
+ * triggers.
+ */
+static void
+ExecSetupTransitionCaptureState(ModifyTableState *mtstate, EState *estate)
+{
+	ModifyTable *plan = (ModifyTable *) mtstate->ps.plan;
+	ResultRelInfo *targetRelInfo = mtstate->rootResultRelInfo;
+
+	/* Check for transition tables on the directly targeted relation. */
+	mtstate->mt_transition_capture =
+		MakeTransitionCaptureState(targetRelInfo->ri_TrigDesc,
+								   RelationGetRelid(targetRelInfo->ri_RelationDesc),
+								   mtstate->operation);
+	if (plan->operation == CMD_INSERT &&
+		plan->onConflictAction == ONCONFLICT_UPDATE)
+		mtstate->mt_oc_transition_capture =
+			MakeTransitionCaptureState(targetRelInfo->ri_TrigDesc,
+									   RelationGetRelid(targetRelInfo->ri_RelationDesc),
+									   CMD_UPDATE);
+}
+
+/*
+ * ExecPrepareTupleRouting --- prepare for routing one tuple
+ *
+ * Determine the partition in which the tuple in slot is to be inserted,
+ * and return its ResultRelInfo in *partRelInfo.  The return value is
+ * a slot holding the tuple of the partition rowtype.
+ *
+ * This also sets the transition table information in mtstate based on the
+ * selected partition.
+ */
+static TupleTableSlot *
+ExecPrepareTupleRouting(ModifyTableState *mtstate,
+						EState *estate,
+						PartitionTupleRouting *proute,
+						ResultRelInfo *targetRelInfo,
+						TupleTableSlot *slot,
+						ResultRelInfo **partRelInfo)
+{
+	ResultRelInfo *partrel;
+	TupleConversionMap *map;
+
+	/*
+	 * Lookup the target partition's ResultRelInfo.  If ExecFindPartition does
+	 * not find a valid partition for the tuple in 'slot' then an error is
+	 * raised.  An error may also be raised if the found partition is not a
+	 * valid target for INSERTs.  This is required since a partitioned table
+	 * UPDATE to another partition becomes a DELETE+INSERT.
+	 */
+	partrel = ExecFindPartition(mtstate, targetRelInfo, proute, slot, estate);
+
+	/*
+	 * If we're capturing transition tuples, we might need to convert from the
+	 * partition rowtype to root partitioned table's rowtype.  But if there
+	 * are no BEFORE triggers on the partition that could change the tuple, we
+	 * can just remember the original unconverted tuple to avoid a needless
+	 * round trip conversion.
+	 */
+	if (mtstate->mt_transition_capture != NULL)
+	{
+		bool		has_before_insert_row_trig;
+
+		has_before_insert_row_trig = (partrel->ri_TrigDesc &&
+									  partrel->ri_TrigDesc->trig_insert_before_row);
+
+		mtstate->mt_transition_capture->tcs_original_insert_tuple =
+			!has_before_insert_row_trig ? slot : NULL;
+	}
+
+	/*
+	 * Convert the tuple, if necessary.
+	 */
+	map = partrel->ri_RootToPartitionMap;
+	if (map != NULL)
+	{
+		TupleTableSlot *new_slot = partrel->ri_PartitionTupleSlot;
+
+		slot = execute_attr_map_slot(map->attrMap, slot, new_slot);
+	}
+
+	*partRelInfo = partrel;
+	return slot;
+}
+
+/* ----------------------------------------------------------------
+ *	   ExecModifyTable
+ *
+ *		Perform table modifications as required, and return RETURNING results
+ *		if needed.
+ * ----------------------------------------------------------------
+ */
+static TupleTableSlot *
+ExecModifyTable(PlanState *pstate)
+{
+	ModifyTableState *node = castNode(ModifyTableState, pstate);
+	ModifyTableContext context;
+	EState	   *estate = node->ps.state;
+	CmdType		operation = node->operation;
+	ResultRelInfo *resultRelInfo;
+	PlanState  *subplanstate;
+	TupleTableSlot *slot;
+	TupleTableSlot *oldSlot;
+	ItemPointerData tuple_ctid;
+	HeapTupleData oldtupdata;
+	HeapTuple	oldtuple;
+	ItemPointer tupleid;
+
+	CHECK_FOR_INTERRUPTS();
+
+	/*
+	 * This should NOT get called during EvalPlanQual; we should have passed a
+	 * subplan tree to EvalPlanQual, instead.  Use a runtime test not just
+	 * Assert because this condition is easy to miss in testing.  (Note:
+	 * although ModifyTable should not get executed within an EvalPlanQual
+	 * operation, we do have to allow it to be initialized and shut down in
+	 * case it is within a CTE subplan.  Hence this test must be here, not in
+	 * ExecInitModifyTable.)
+	 */
+	if (estate->es_epq_active != NULL)
+		elog(ERROR, "ModifyTable should not be called during EvalPlanQual");
+
+	/*
+	 * If we've already completed processing, don't try to do more.  We need
+	 * this test because ExecPostprocessPlan might call us an extra time, and
+	 * our subplan's nodes aren't necessarily robust against being called
+	 * extra times.
+	 */
+	if (node->mt_done)
+		return NULL;
+
+	/*
+	 * On first call, fire BEFORE STATEMENT triggers before proceeding.
+	 */
+	if (node->fireBSTriggers)
+	{
+		fireBSTriggers(node);
+		node->fireBSTriggers = false;
+	}
+
+	/* Preload local variables */
+	resultRelInfo = node->resultRelInfo + node->mt_lastResultIndex;
+	subplanstate = outerPlanState(node);
+
+	/* Set global context */
+	context.mtstate = node;
+	context.epqstate = &node->mt_epqstate;
+	context.estate = estate;
+
+	/*
+	 * Fetch rows from subplan, and execute the required table modification
+	 * for each row.
+	 */
+	for (;;)
+	{
+		/*
+		 * Reset the per-output-tuple exprcontext.  This is needed because
+		 * triggers expect to use that context as workspace.  It's a bit ugly
+		 * to do this below the top level of the plan, however.  We might need
+		 * to rethink this later.
+		 */
+		ResetPerTupleExprContext(estate);
+
+		/*
+		 * Reset per-tuple memory context used for processing on conflict and
+		 * returning clauses, to free any expression evaluation storage
+		 * allocated in the previous cycle.
+		 */
+		if (pstate->ps_ExprContext)
+			ResetExprContext(pstate->ps_ExprContext);
+
+		context.planSlot = ExecProcNode(subplanstate);
+
+		/* No more tuples to process? */
+		if (TupIsNull(context.planSlot))
+			break;
+
+		/*
+		 * When there are multiple result relations, each tuple contains a
+		 * junk column that gives the OID of the rel from which it came.
+		 * Extract it and select the correct result relation.
+		 */
+		if (AttributeNumberIsValid(node->mt_resultOidAttno))
+		{
+			Datum		datum;
+			bool		isNull;
+			Oid			resultoid;
+
+			datum = ExecGetJunkAttribute(context.planSlot, node->mt_resultOidAttno,
+										 &isNull);
+			if (isNull)
+			{
+				/*
+				 * For commands other than MERGE, any tuples having InvalidOid
+				 * for tableoid are errors.  For MERGE, we may need to handle
+				 * them as WHEN NOT MATCHED clauses if any, so do that.
+				 *
+				 * Note that we use the node's toplevel resultRelInfo, not any
+				 * specific partition's.
+				 */
+				if (operation == CMD_MERGE)
+				{
+					EvalPlanQualSetSlot(&node->mt_epqstate, context.planSlot);
+
+					ExecMerge(&context, node->resultRelInfo, NULL, node->canSetTag);
+					continue;	/* no RETURNING support yet */
+				}
+
+				elog(ERROR, "tableoid is NULL");
+			}
+			resultoid = DatumGetObjectId(datum);
+
+			/* If it's not the same as last time, we need to locate the rel */
+			if (resultoid != node->mt_lastResultOid)
+				resultRelInfo = ExecLookupResultRelByOid(node, resultoid,
+														 false, true);
+		}
+
+		/*
+		 * If resultRelInfo->ri_usesFdwDirectModify is true, all we need to do
+		 * here is compute the RETURNING expressions.
+		 */
+		if (resultRelInfo->ri_usesFdwDirectModify)
+		{
+			Assert(resultRelInfo->ri_projectReturning);
+
+			/*
+			 * A scan slot containing the data that was actually inserted,
+			 * updated or deleted has already been made available to
+			 * ExecProcessReturning by IterateDirectModify, so no need to
+			 * provide it here.
+			 */
+			slot = ExecProcessReturning(resultRelInfo, NULL, context.planSlot);
+
+			return slot;
+		}
+
+		EvalPlanQualSetSlot(&node->mt_epqstate, context.planSlot);
+		slot = context.planSlot;
+
+		tupleid = NULL;
+		oldtuple = NULL;
+
+		/*
+		 * For UPDATE/DELETE/MERGE, fetch the row identity info for the tuple
+		 * to be updated/deleted/merged.  For a heap relation, that's a TID;
+		 * otherwise we may have a wholerow junk attr that carries the old
+		 * tuple in toto.  Keep this in step with the part of
+		 * ExecInitModifyTable that sets up ri_RowIdAttNo.
+		 */
+		if (operation == CMD_UPDATE || operation == CMD_DELETE ||
+			operation == CMD_MERGE)
+		{
+			char		relkind;
+			Datum		datum;
+			bool		isNull;
+
+			relkind = resultRelInfo->ri_RelationDesc->rd_rel->relkind;
+			if (relkind == RELKIND_RELATION ||
+				relkind == RELKIND_MATVIEW ||
+				relkind == RELKIND_PARTITIONED_TABLE)
+			{
+				/* ri_RowIdAttNo refers to a ctid attribute */
+				Assert(AttributeNumberIsValid(resultRelInfo->ri_RowIdAttNo));
+				datum = ExecGetJunkAttribute(slot,
+											 resultRelInfo->ri_RowIdAttNo,
+											 &isNull);
+
+				/*
+				 * For commands other than MERGE, any tuples having a null row
+				 * identifier are errors.  For MERGE, we may need to handle
+				 * them as WHEN NOT MATCHED clauses if any, so do that.
+				 *
+				 * Note that we use the node's toplevel resultRelInfo, not any
+				 * specific partition's.
+				 */
+				if (isNull)
+				{
+					if (operation == CMD_MERGE)
+					{
+						EvalPlanQualSetSlot(&node->mt_epqstate, context.planSlot);
+
+						ExecMerge(&context, node->resultRelInfo, NULL, node->canSetTag);
+						continue;	/* no RETURNING support yet */
+					}
+
+					elog(ERROR, "ctid is NULL");
+				}
+
+				tupleid = (ItemPointer) DatumGetPointer(datum);
+				tuple_ctid = *tupleid;	/* be sure we don't free ctid!! */
+				tupleid = &tuple_ctid;
+			}
+
+			/*
+			 * Use the wholerow attribute, when available, to reconstruct the
+			 * old relation tuple.  The old tuple serves one or both of two
+			 * purposes: 1) it serves as the OLD tuple for row triggers, 2) it
+			 * provides values for any unchanged columns for the NEW tuple of
+			 * an UPDATE, because the subplan does not produce all the columns
+			 * of the target table.
+			 *
+			 * Note that the wholerow attribute does not carry system columns,
+			 * so foreign table triggers miss seeing those, except that we
+			 * know enough here to set t_tableOid.  Quite separately from
+			 * this, the FDW may fetch its own junk attrs to identify the row.
+			 *
+			 * Other relevant relkinds, currently limited to views, always
+			 * have a wholerow attribute.
+			 */
+			else if (AttributeNumberIsValid(resultRelInfo->ri_RowIdAttNo))
+			{
+				datum = ExecGetJunkAttribute(slot,
+											 resultRelInfo->ri_RowIdAttNo,
+											 &isNull);
+				/* shouldn't ever get a null result... */
+				if (isNull)
+					elog(ERROR, "wholerow is NULL");
+
+				oldtupdata.t_data = DatumGetHeapTupleHeader(datum);
+				oldtupdata.t_len =
+					HeapTupleHeaderGetDatumLength(oldtupdata.t_data);
+				ItemPointerSetInvalid(&(oldtupdata.t_self));
+				/* Historically, view triggers see invalid t_tableOid. */
+				oldtupdata.t_tableOid =
+					(relkind == RELKIND_VIEW) ? InvalidOid :
+					RelationGetRelid(resultRelInfo->ri_RelationDesc);
+
+				oldtuple = &oldtupdata;
+			}
+			else
+			{
+				/* Only foreign tables are allowed to omit a row-ID attr */
+				Assert(relkind == RELKIND_FOREIGN_TABLE);
+			}
+		}
+
+		switch (operation)
+		{
+			case CMD_INSERT:
+				/* Initialize projection info if first time for this table */
+				if (unlikely(!resultRelInfo->ri_projectNewInfoValid))
+					ExecInitInsertProjection(node, resultRelInfo);
+				slot = ExecGetInsertNewTuple(resultRelInfo, context.planSlot);
+				slot = ExecInsert(&context, resultRelInfo, slot,
+								  node->canSetTag, NULL, NULL);
+				break;
+
+			case CMD_UPDATE:
+				/* Initialize projection info if first time for this table */
+				if (unlikely(!resultRelInfo->ri_projectNewInfoValid))
+					ExecInitUpdateProjection(node, resultRelInfo);
+
+				/*
+				 * Make the new tuple by combining plan's output tuple with
+				 * the old tuple being updated.
+				 */
+				oldSlot = resultRelInfo->ri_oldTupleSlot;
+				if (oldtuple != NULL)
+				{
+					/* Use the wholerow junk attr as the old tuple. */
+					ExecForceStoreHeapTuple(oldtuple, oldSlot, false);
+				}
+				else
+				{
+					/* Fetch the most recent version of old tuple. */
+					Relation	relation = resultRelInfo->ri_RelationDesc;
+
+					if (!table_tuple_fetch_row_version(relation, tupleid,
+													   SnapshotAny,
+													   oldSlot))
+						elog(ERROR, "failed to fetch tuple being updated");
+				}
+				slot = ExecGetUpdateNewTuple(resultRelInfo, context.planSlot,
+											 oldSlot);
+				context.relaction = NULL;
+
+				/* Now apply the update. */
+				slot = ExecUpdate(&context, resultRelInfo, tupleid, oldtuple,
+								  slot, node->canSetTag);
+				break;
+
+			case CMD_DELETE:
+				slot = ExecDelete(&context, resultRelInfo, tupleid, oldtuple,
+								  true, false, node->canSetTag, NULL, NULL);
+				break;
+
+			case CMD_MERGE:
+				slot = ExecMerge(&context, resultRelInfo, tupleid, node->canSetTag);
+				break;
+
+			default:
+				elog(ERROR, "unknown operation");
+				break;
+		}
+
+		/*
+		 * If we got a RETURNING result, return it to caller.  We'll continue
+		 * the work on next call.
+		 */
+		if (slot)
+			return slot;
+	}
+
+	/*
+	 * Insert remaining tuples for batch insert.
+	 */
+	if (estate->es_insert_pending_result_relations != NIL)
+		ExecPendingInserts(estate);
+
+	/*
+	 * We're done, but fire AFTER STATEMENT triggers before exiting.
+	 */
+	fireASTriggers(node);
+
+	node->mt_done = true;
+
+	return NULL;
+}
+
+/*
+ * ExecLookupResultRelByOid
+ * 		If the table with given OID is among the result relations to be
+ * 		updated by the given ModifyTable node, return its ResultRelInfo.
+ *
+ * If not found, return NULL if missing_ok, else raise error.
+ *
+ * If update_cache is true, then upon successful lookup, update the node's
+ * one-element cache.  ONLY ExecModifyTable may pass true for this.
+ */
+ResultRelInfo *
+ExecLookupResultRelByOid(ModifyTableState *node, Oid resultoid,
+						 bool missing_ok, bool update_cache)
+{
+	if (node->mt_resultOidHash)
+	{
+		/* Use the pre-built hash table to locate the rel */
+		MTTargetRelLookup *mtlookup;
+
+		mtlookup = (MTTargetRelLookup *)
+			hash_search(node->mt_resultOidHash, &resultoid, HASH_FIND, NULL);
+		if (mtlookup)
+		{
+			if (update_cache)
+			{
+				node->mt_lastResultOid = resultoid;
+				node->mt_lastResultIndex = mtlookup->relationIndex;
+			}
+			return node->resultRelInfo + mtlookup->relationIndex;
+		}
+	}
+	else
+	{
+		/* With few target rels, just search the ResultRelInfo array */
+		for (int ndx = 0; ndx < node->mt_nrels; ndx++)
+		{
+			ResultRelInfo *rInfo = node->resultRelInfo + ndx;
+
+			if (RelationGetRelid(rInfo->ri_RelationDesc) == resultoid)
+			{
+				if (update_cache)
+				{
+					node->mt_lastResultOid = resultoid;
+					node->mt_lastResultIndex = ndx;
+				}
+				return rInfo;
+			}
+		}
+	}
+
+	if (!missing_ok)
+		elog(ERROR, "incorrect result relation OID %u", resultoid);
+	return NULL;
+}
+
+/* ----------------------------------------------------------------
+ *		ExecInitModifyTable
+ * ----------------------------------------------------------------
+ */
+ModifyTableState *
+ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
+{
+	ModifyTableState *mtstate;
+	Plan	   *subplan = outerPlan(node);
+	CmdType		operation = node->operation;
+	int			nrels = list_length(node->resultRelations);
+	ResultRelInfo *resultRelInfo;
+	List	   *arowmarks;
+	ListCell   *l;
+	int			i;
+	Relation	rel;
+
+	/* check for unsupported flags */
+	Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK)));
+
+	/*
+	 * create state structure
+	 */
+	mtstate = makeNode(ModifyTableState);
+	mtstate->ps.plan = (Plan *) node;
+	mtstate->ps.state = estate;
+	mtstate->ps.ExecProcNode = ExecModifyTable;
+
+	mtstate->operation = operation;
+	mtstate->canSetTag = node->canSetTag;
+	mtstate->mt_done = false;
+
+	mtstate->mt_nrels = nrels;
+	mtstate->resultRelInfo = (ResultRelInfo *)
+		palloc(nrels * sizeof(ResultRelInfo));
+
+	mtstate->mt_merge_inserted = 0;
+	mtstate->mt_merge_updated = 0;
+	mtstate->mt_merge_deleted = 0;
+
+	/*----------
+	 * Resolve the target relation. This is the same as:
+	 *
+	 * - the relation for which we will fire FOR STATEMENT triggers,
+	 * - the relation into whose tuple format all captured transition tuples
+	 *   must be converted, and
+	 * - the root partitioned table used for tuple routing.
+	 *
+	 * If it's a partitioned or inherited table, the root partition or
+	 * appendrel RTE doesn't appear elsewhere in the plan and its RT index is
+	 * given explicitly in node->rootRelation.  Otherwise, the target relation
+	 * is the sole relation in the node->resultRelations list.
+	 *----------
+	 */
+	if (node->rootRelation > 0)
+	{
+		mtstate->rootResultRelInfo = makeNode(ResultRelInfo);
+		ExecInitResultRelation(estate, mtstate->rootResultRelInfo,
+							   node->rootRelation);
+	}
+	else
+	{
+		Assert(list_length(node->resultRelations) == 1);
+		mtstate->rootResultRelInfo = mtstate->resultRelInfo;
+		ExecInitResultRelation(estate, mtstate->resultRelInfo,
+							   linitial_int(node->resultRelations));
+	}
+
+	/* set up epqstate with dummy subplan data for the moment */
+	EvalPlanQualInitExt(&mtstate->mt_epqstate, estate, NULL, NIL,
+						node->epqParam, node->resultRelations);
+	mtstate->fireBSTriggers = true;
+
+	/*
+	 * Build state for collecting transition tuples.  This requires having a
+	 * valid trigger query context, so skip it in explain-only mode.
+	 */
+	if (!(eflags & EXEC_FLAG_EXPLAIN_ONLY))
+		ExecSetupTransitionCaptureState(mtstate, estate);
+
+	/*
+	 * Open all the result relations and initialize the ResultRelInfo structs.
+	 * (But root relation was initialized above, if it's part of the array.)
+	 * We must do this before initializing the subplan, because direct-modify
+	 * FDWs expect their ResultRelInfos to be available.
+	 */
+	resultRelInfo = mtstate->resultRelInfo;
+	i = 0;
+	foreach(l, node->resultRelations)
+	{
+		Index		resultRelation = lfirst_int(l);
+
+		if (resultRelInfo != mtstate->rootResultRelInfo)
+		{
+			ExecInitResultRelation(estate, resultRelInfo, resultRelation);
+
+			/*
+			 * For child result relations, store the root result relation
+			 * pointer.  We do so for the convenience of places that want to
+			 * look at the query's original target relation but don't have the
+			 * mtstate handy.
+			 */
+			resultRelInfo->ri_RootResultRelInfo = mtstate->rootResultRelInfo;
+		}
+
+		/* Initialize the usesFdwDirectModify flag */
+		resultRelInfo->ri_usesFdwDirectModify =
+			bms_is_member(i, node->fdwDirectModifyPlans);
+
+		/*
+		 * Verify result relation is a valid target for the current operation
+		 */
+		CheckValidResultRel(resultRelInfo, operation);
+
+		resultRelInfo++;
+		i++;
+	}
+
+	/*
+	 * Now we may initialize the subplan.
+	 */
+	outerPlanState(mtstate) = ExecInitNode(subplan, estate, eflags);
+
+	/*
+	 * Do additional per-result-relation initialization.
+	 */
+	for (i = 0; i < nrels; i++)
+	{
+		resultRelInfo = &mtstate->resultRelInfo[i];
+
+		/* Let FDWs init themselves for foreign-table result rels */
+		if (!resultRelInfo->ri_usesFdwDirectModify &&
+			resultRelInfo->ri_FdwRoutine != NULL &&
+			resultRelInfo->ri_FdwRoutine->BeginForeignModify != NULL)
+		{
+			List	   *fdw_private = (List *) list_nth(node->fdwPrivLists, i);
+
+			resultRelInfo->ri_FdwRoutine->BeginForeignModify(mtstate,
+															 resultRelInfo,
+															 fdw_private,
+															 i,
+															 eflags);
+		}
+
+		/*
+		 * For UPDATE/DELETE/MERGE, find the appropriate junk attr now, either
+		 * a 'ctid' or 'wholerow' attribute depending on relkind.  For foreign
+		 * tables, the FDW might have created additional junk attr(s), but
+		 * those are no concern of ours.
+		 */
+		if (operation == CMD_UPDATE || operation == CMD_DELETE ||
+			operation == CMD_MERGE)
+		{
+			char		relkind;
+
+			relkind = resultRelInfo->ri_RelationDesc->rd_rel->relkind;
+			if (relkind == RELKIND_RELATION ||
+				relkind == RELKIND_MATVIEW ||
+				relkind == RELKIND_PARTITIONED_TABLE)
+			{
+				resultRelInfo->ri_RowIdAttNo =
+					ExecFindJunkAttributeInTlist(subplan->targetlist, "ctid");
+				if (!AttributeNumberIsValid(resultRelInfo->ri_RowIdAttNo))
+					elog(ERROR, "could not find junk ctid column");
+			}
+			else if (relkind == RELKIND_FOREIGN_TABLE)
+			{
+				/*
+				 * We don't support MERGE with foreign tables for now.  (It's
+				 * problematic because the implementation uses CTID.)
+				 */
+				Assert(operation != CMD_MERGE);
+
+				/*
+				 * When there is a row-level trigger, there should be a
+				 * wholerow attribute.  We also require it to be present in
+				 * UPDATE and MERGE, so we can get the values of unchanged
+				 * columns.
+				 */
+				resultRelInfo->ri_RowIdAttNo =
+					ExecFindJunkAttributeInTlist(subplan->targetlist,
+												 "wholerow");
+				if ((mtstate->operation == CMD_UPDATE || mtstate->operation == CMD_MERGE) &&
+					!AttributeNumberIsValid(resultRelInfo->ri_RowIdAttNo))
+					elog(ERROR, "could not find junk wholerow column");
+			}
+			else
+			{
+				/* No support for MERGE */
+				Assert(operation != CMD_MERGE);
+				/* Other valid target relkinds must provide wholerow */
+				resultRelInfo->ri_RowIdAttNo =
+					ExecFindJunkAttributeInTlist(subplan->targetlist,
+												 "wholerow");
+				if (!AttributeNumberIsValid(resultRelInfo->ri_RowIdAttNo))
+					elog(ERROR, "could not find junk wholerow column");
+			}
+		}
+
+		/*
+		 * For INSERT/UPDATE/MERGE, prepare to evaluate any generated columns.
+		 * We must do this now, even if we never insert or update any rows, to
+		 * cover the case where a MERGE does some UPDATE operations and later
+		 * some INSERTs.  We'll need ri_GeneratedExprs to cover all generated
+		 * columns, so we force it now.  (It might be sufficient to do this
+		 * only for operation == CMD_MERGE, but we'll avoid changing the data
+		 * structure definition in back branches.)
+		 */
+		if (operation == CMD_INSERT || operation == CMD_UPDATE || operation == CMD_MERGE)
+			ExecInitStoredGenerated(resultRelInfo, estate, operation);
+	}
+
+	/*
+	 * If this is an inherited update/delete/merge, there will be a junk
+	 * attribute named "tableoid" present in the subplan's targetlist.  It
+	 * will be used to identify the result relation for a given tuple to be
+	 * updated/deleted/merged.
+	 */
+	mtstate->mt_resultOidAttno =
+		ExecFindJunkAttributeInTlist(subplan->targetlist, "tableoid");
+	Assert(AttributeNumberIsValid(mtstate->mt_resultOidAttno) || nrels == 1);
+	mtstate->mt_lastResultOid = InvalidOid; /* force lookup at first tuple */
+	mtstate->mt_lastResultIndex = 0;	/* must be zero if no such attr */
+
+	/* Get the root target relation */
+	rel = mtstate->rootResultRelInfo->ri_RelationDesc;
+
+	/*
+	 * Build state for tuple routing if it's a partitioned INSERT.  An UPDATE
+	 * or MERGE might need this too, but only if it actually moves tuples
+	 * between partitions; in that case setup is done by
+	 * ExecCrossPartitionUpdate.
+	 */
+	if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE &&
+		operation == CMD_INSERT)
+		mtstate->mt_partition_tuple_routing =
+			ExecSetupPartitionTupleRouting(estate, rel);
+
+	/*
+	 * Initialize any WITH CHECK OPTION constraints if needed.
+	 */
+	resultRelInfo = mtstate->resultRelInfo;
+	foreach(l, node->withCheckOptionLists)
+	{
+		List	   *wcoList = (List *) lfirst(l);
+		List	   *wcoExprs = NIL;
+		ListCell   *ll;
+
+		foreach(ll, wcoList)
+		{
+			WithCheckOption *wco = (WithCheckOption *) lfirst(ll);
+			ExprState  *wcoExpr = ExecInitQual((List *) wco->qual,
+											   &mtstate->ps);
+
+			wcoExprs = lappend(wcoExprs, wcoExpr);
+		}
+
+		resultRelInfo->ri_WithCheckOptions = wcoList;
+		resultRelInfo->ri_WithCheckOptionExprs = wcoExprs;
+		resultRelInfo++;
+	}
+
+	/*
+	 * Initialize RETURNING projections if needed.
+	 */
+	if (node->returningLists)
+	{
+		TupleTableSlot *slot;
+		ExprContext *econtext;
+
+		/*
+		 * Initialize result tuple slot and assign its rowtype using the first
+		 * RETURNING list.  We assume the rest will look the same.
+		 */
+		mtstate->ps.plan->targetlist = (List *) linitial(node->returningLists);
+
+		/* Set up a slot for the output of the RETURNING projection(s) */
+		ExecInitResultTupleSlotTL(&mtstate->ps, &TTSOpsVirtual);
+		slot = mtstate->ps.ps_ResultTupleSlot;
+
+		/* Need an econtext too */
+		if (mtstate->ps.ps_ExprContext == NULL)
+			ExecAssignExprContext(estate, &mtstate->ps);
+		econtext = mtstate->ps.ps_ExprContext;
+
+		/*
+		 * Build a projection for each result rel.
+		 */
+		resultRelInfo = mtstate->resultRelInfo;
+		foreach(l, node->returningLists)
+		{
+			List	   *rlist = (List *) lfirst(l);
+
+			resultRelInfo->ri_returningList = rlist;
+			resultRelInfo->ri_projectReturning =
+				ExecBuildProjectionInfo(rlist, econtext, slot, &mtstate->ps,
+										resultRelInfo->ri_RelationDesc->rd_att);
+			resultRelInfo++;
+		}
+	}
+	else
+	{
+		/*
+		 * We still must construct a dummy result tuple type, because InitPlan
+		 * expects one (maybe should change that?).
+		 */
+		mtstate->ps.plan->targetlist = NIL;
+		ExecInitResultTypeTL(&mtstate->ps);
+
+		mtstate->ps.ps_ExprContext = NULL;
+	}
+
+	/* Set the list of arbiter indexes if needed for ON CONFLICT */
+	resultRelInfo = mtstate->resultRelInfo;
+	if (node->onConflictAction != ONCONFLICT_NONE)
+	{
+		/* insert may only have one relation, inheritance is not expanded */
+		Assert(nrels == 1);
+		resultRelInfo->ri_onConflictArbiterIndexes = node->arbiterIndexes;
+	}
+
+	/*
+	 * If needed, Initialize target list, projection and qual for ON CONFLICT
+	 * DO UPDATE.
+	 */
+	if (node->onConflictAction == ONCONFLICT_UPDATE)
+	{
+		OnConflictSetState *onconfl = makeNode(OnConflictSetState);
+		ExprContext *econtext;
+		TupleDesc	relationDesc;
+
+		/* already exists if created by RETURNING processing above */
+		if (mtstate->ps.ps_ExprContext == NULL)
+			ExecAssignExprContext(estate, &mtstate->ps);
+
+		econtext = mtstate->ps.ps_ExprContext;
+		relationDesc = resultRelInfo->ri_RelationDesc->rd_att;
+
+		/* create state for DO UPDATE SET operation */
+		resultRelInfo->ri_onConflict = onconfl;
+
+		/* initialize slot for the existing tuple */
+		onconfl->oc_Existing =
+			table_slot_create(resultRelInfo->ri_RelationDesc,
+							  &mtstate->ps.state->es_tupleTable);
+
+		/*
+		 * Create the tuple slot for the UPDATE SET projection. We want a slot
+		 * of the table's type here, because the slot will be used to insert
+		 * into the table, and for RETURNING processing - which may access
+		 * system attributes.
+		 */
+		onconfl->oc_ProjSlot =
+			table_slot_create(resultRelInfo->ri_RelationDesc,
+							  &mtstate->ps.state->es_tupleTable);
+
+		/* build UPDATE SET projection state */
+		onconfl->oc_ProjInfo =
+			ExecBuildUpdateProjection(node->onConflictSet,
+									  true,
+									  node->onConflictCols,
+									  relationDesc,
+									  econtext,
+									  onconfl->oc_ProjSlot,
+									  &mtstate->ps);
+
+		/* initialize state to evaluate the WHERE clause, if any */
+		if (node->onConflictWhere)
+		{
+			ExprState  *qualexpr;
+
+			qualexpr = ExecInitQual((List *) node->onConflictWhere,
+									&mtstate->ps);
+			onconfl->oc_WhereClause = qualexpr;
+		}
+	}
+
+	/*
+	 * If we have any secondary relations in an UPDATE or DELETE, they need to
+	 * be treated like non-locked relations in SELECT FOR UPDATE, i.e., the
+	 * EvalPlanQual mechanism needs to be told about them.  This also goes for
+	 * the source relations in a MERGE.  Locate the relevant ExecRowMarks.
+	 */
+	arowmarks = NIL;
+	foreach(l, node->rowMarks)
+	{
+		PlanRowMark *rc = lfirst_node(PlanRowMark, l);
+		ExecRowMark *erm;
+		ExecAuxRowMark *aerm;
+
+		/* ignore "parent" rowmarks; they are irrelevant at runtime */
+		if (rc->isParent)
+			continue;
+
+		/* Find ExecRowMark and build ExecAuxRowMark */
+		erm = ExecFindRowMark(estate, rc->rti, false);
+		aerm = ExecBuildAuxRowMark(erm, subplan->targetlist);
+		arowmarks = lappend(arowmarks, aerm);
+	}
+
+	/* For a MERGE command, initialize its state */
+	if (mtstate->operation == CMD_MERGE)
+		ExecInitMerge(mtstate, estate);
+
+	EvalPlanQualSetPlan(&mtstate->mt_epqstate, subplan, arowmarks);
+
+	/*
+	 * If there are a lot of result relations, use a hash table to speed the
+	 * lookups.  If there are not a lot, a simple linear search is faster.
+	 *
+	 * It's not clear where the threshold is, but try 64 for starters.  In a
+	 * debugging build, use a small threshold so that we get some test
+	 * coverage of both code paths.
+	 */
+#ifdef USE_ASSERT_CHECKING
+#define MT_NRELS_HASH 4
+#else
+#define MT_NRELS_HASH 64
+#endif
+	if (nrels >= MT_NRELS_HASH)
+	{
+		HASHCTL		hash_ctl;
+
+		hash_ctl.keysize = sizeof(Oid);
+		hash_ctl.entrysize = sizeof(MTTargetRelLookup);
+		hash_ctl.hcxt = CurrentMemoryContext;
+		mtstate->mt_resultOidHash =
+			hash_create("ModifyTable target hash",
+						nrels, &hash_ctl,
+						HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
+		for (i = 0; i < nrels; i++)
+		{
+			Oid			hashkey;
+			MTTargetRelLookup *mtlookup;
+			bool		found;
+
+			resultRelInfo = &mtstate->resultRelInfo[i];
+			hashkey = RelationGetRelid(resultRelInfo->ri_RelationDesc);
+			mtlookup = (MTTargetRelLookup *)
+				hash_search(mtstate->mt_resultOidHash, &hashkey,
+							HASH_ENTER, &found);
+			Assert(!found);
+			mtlookup->relationIndex = i;
+		}
+	}
+	else
+		mtstate->mt_resultOidHash = NULL;
+
+	/*
+	 * 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).
+	 *
+	 * We only do this for INSERT, so that for UPDATE/DELETE the batch size
+	 * remains set to 0.
+	 */
+	if (operation == CMD_INSERT)
+	{
+		/* insert may only have one relation, inheritance is not expanded */
+		Assert(nrels == 1);
+		resultRelInfo = mtstate->resultRelInfo;
+		if (!resultRelInfo->ri_usesFdwDirectModify &&
+			resultRelInfo->ri_FdwRoutine != NULL &&
+			resultRelInfo->ri_FdwRoutine->GetForeignModifyBatchSize &&
+			resultRelInfo->ri_FdwRoutine->ExecForeignBatchInsert)
+		{
+			resultRelInfo->ri_BatchSize =
+				resultRelInfo->ri_FdwRoutine->GetForeignModifyBatchSize(resultRelInfo);
+			Assert(resultRelInfo->ri_BatchSize >= 1);
+		}
+		else
+			resultRelInfo->ri_BatchSize = 1;
+	}
+
+	/*
+	 * Lastly, if this is not the primary (canSetTag) ModifyTable node, add it
+	 * to estate->es_auxmodifytables so that it will be run to completion by
+	 * ExecPostprocessPlan.  (It'd actually work fine to add the primary
+	 * ModifyTable node too, but there's no need.)  Note the use of lcons not
+	 * lappend: we need later-initialized ModifyTable nodes to be shut down
+	 * before earlier ones.  This ensures that we don't throw away RETURNING
+	 * rows that need to be seen by a later CTE subplan.
+	 */
+	if (!mtstate->canSetTag)
+		estate->es_auxmodifytables = lcons(mtstate,
+										   estate->es_auxmodifytables);
+
+	return mtstate;
+}
+
+/* ----------------------------------------------------------------
+ *		ExecEndModifyTable
+ *
+ *		Shuts down the plan.
+ *
+ *		Returns nothing of interest.
+ * ----------------------------------------------------------------
+ */
+void
+ExecEndModifyTable(ModifyTableState *node)
+{
+	int			i;
+
+	/*
+	 * Allow any FDWs to shut down
+	 */
+	for (i = 0; i < node->mt_nrels; i++)
+	{
+		int			j;
+		ResultRelInfo *resultRelInfo = node->resultRelInfo + i;
+
+		if (!resultRelInfo->ri_usesFdwDirectModify &&
+			resultRelInfo->ri_FdwRoutine != NULL &&
+			resultRelInfo->ri_FdwRoutine->EndForeignModify != NULL)
+			resultRelInfo->ri_FdwRoutine->EndForeignModify(node->ps.state,
+														   resultRelInfo);
+
+		/*
+		 * Cleanup the initialized batch slots. This only matters for FDWs
+		 * with batching, but the other cases will have ri_NumSlotsInitialized
+		 * == 0.
+		 */
+		for (j = 0; j < resultRelInfo->ri_NumSlotsInitialized; j++)
+		{
+			ExecDropSingleTupleTableSlot(resultRelInfo->ri_Slots[j]);
+			ExecDropSingleTupleTableSlot(resultRelInfo->ri_PlanSlots[j]);
+		}
+	}
+
+	/*
+	 * Close all the partitioned tables, leaf partitions, and their indices
+	 * and release the slot used for tuple routing, if set.
+	 */
+	if (node->mt_partition_tuple_routing)
+	{
+		ExecCleanupTupleRouting(node, node->mt_partition_tuple_routing);
+
+		if (node->mt_root_tuple_slot)
+			ExecDropSingleTupleTableSlot(node->mt_root_tuple_slot);
+	}
+
+	/*
+	 * Free the exprcontext
+	 */
+	ExecFreeExprContext(&node->ps);
+
+	/*
+	 * clean out the tuple table
+	 */
+	if (node->ps.ps_ResultTupleSlot)
+		ExecClearTuple(node->ps.ps_ResultTupleSlot);
+
+	/*
+	 * Terminate EPQ execution if active
+	 */
+	EvalPlanQualEnd(&node->mt_epqstate);
+
+	/*
+	 * shut down subplan
+	 */
+	ExecEndNode(outerPlanState(node));
+}
+
+void
+ExecReScanModifyTable(ModifyTableState *node)
+{
+	/*
+	 * Currently, we don't need to support rescan on ModifyTable nodes. The
+	 * semantics of that would be a bit debatable anyway.
+	 */
+	elog(ERROR, "ExecReScanModifyTable is not implemented");
+}