Centralize executor's opening/closing of Relations for rangetable entries.

Create an array estate->es_relations[] paralleling the es_range_table,
and store references to Relations (relcache entries) there, so that any
given RT entry is opened and closed just once per executor run.  Scan
nodes typically still call ExecOpenScanRelation, but ExecCloseScanRelation
is no more; relation closing is now done centrally in ExecEndPlan.

This is slightly more complex than one would expect because of the
interactions with relcache references held in ResultRelInfo nodes.
The general convention is now that ResultRelInfo->ri_RelationDesc does
not represent a separate relcache reference and so does not need to be
explicitly closed; but there is an exception for ResultRelInfos in the
es_trig_target_relations list, which are manufactured by
ExecGetTriggerResultRel and have to be cleaned up by
ExecCleanUpTriggerState.  (That much was true all along, but these
ResultRelInfos are now more different from others than they used to be.)

To allow the partition pruning logic to make use of es_relations[] rather
than having its own relcache references, adjust PartitionedRelPruneInfo
to store an RT index rather than a relation OID.

Amit Langote, reviewed by David Rowley and Jesper Pedersen,
some mods by me

Discussion: https://postgr.es/m/468c85d9-540e-66a2-1dde-fec2b741e688@lab.ntt.co.jp

contrib/postgres_fdw/postgres_fdw.c

@@ -2546,10 +2546,6 @@ postgresEndDirectModify(ForeignScanState *node)
 	ReleaseConnection(dmstate->conn);
 	dmstate->conn = NULL;
 
-	/* close the target relation. */
-	if (dmstate->resultRel)
-		ExecCloseScanRelation(dmstate->resultRel);
-
 	/* MemoryContext will be deleted automatically. */
 }
 

src/backend/catalog/indexing.c

@@ -42,7 +42,7 @@ CatalogOpenIndexes(Relation heapRel)
 	ResultRelInfo *resultRelInfo;
 
 	resultRelInfo = makeNode(ResultRelInfo);
-	resultRelInfo->ri_RangeTableIndex = 1;	/* dummy */
+	resultRelInfo->ri_RangeTableIndex = 0;	/* dummy */
 	resultRelInfo->ri_RelationDesc = heapRel;
 	resultRelInfo->ri_TrigDesc = NULL;	/* we don't fire triggers */
 

src/backend/commands/copy.c

@@ -2471,7 +2471,7 @@ CopyFrom(CopyState cstate)
 	resultRelInfo = makeNode(ResultRelInfo);
 	InitResultRelInfo(resultRelInfo,
 					  cstate->rel,
-					  1,		/* dummy rangetable index */
+					  1,		/* must match rel's position in range_table */
 					  NULL,
 					  0);
 	target_resultRelInfo = resultRelInfo;
@@ -2485,6 +2485,8 @@ CopyFrom(CopyState cstate)
 	estate->es_num_result_relations = 1;
 	estate->es_result_relation_info = resultRelInfo;
 	estate->es_range_table = cstate->range_table;
+	estate->es_relations = (Relation *) palloc0(list_length(cstate->range_table) *
+												sizeof(Relation));
 
 	/* Set up a tuple slot too */
 	myslot = ExecInitExtraTupleSlot(estate, tupDesc);

src/backend/executor/execMain.c

@@ -824,6 +824,15 @@ InitPlan(QueryDesc *queryDesc, int eflags)
 	 * initialize the node's execution state
 	 */
 	estate->es_range_table = rangeTable;
+
+	/*
+	 * Allocate an array to store an open Relation corresponding to each
+	 * rangeTable item, and initialize entries to NULL.  Relations are opened
+	 * and stored here as needed.
+	 */
+	estate->es_relations = (Relation *) palloc0(list_length(rangeTable) *
+												sizeof(Relation));
+
 	estate->es_plannedstmt = plannedstmt;
 
 	/*
@@ -845,13 +854,10 @@ InitPlan(QueryDesc *queryDesc, int eflags)
 		foreach(l, resultRelations)
 		{
 			Index		resultRelationIndex = lfirst_int(l);
-			Oid			resultRelationOid;
 			Relation	resultRelation;
 
-			resultRelationOid = getrelid(resultRelationIndex, rangeTable);
+			resultRelation = ExecGetRangeTableRelation(estate,
-			resultRelation = heap_open(resultRelationOid, NoLock);
+													   resultRelationIndex);
-			Assert(CheckRelationLockedByMe(resultRelation, RowExclusiveLock, true));
-
 			InitResultRelInfo(resultRelInfo,
 							  resultRelation,
 							  resultRelationIndex,
@@ -886,15 +892,13 @@ InitPlan(QueryDesc *queryDesc, int eflags)
 			foreach(l, plannedstmt->rootResultRelations)
 			{
 				Index		resultRelIndex = lfirst_int(l);
-				Oid			resultRelOid;
 				Relation	resultRelDesc;
 
-				resultRelOid = getrelid(resultRelIndex, rangeTable);
+				resultRelDesc = ExecGetRangeTableRelation(estate,
-				resultRelDesc = heap_open(resultRelOid, NoLock);
+														  resultRelIndex);
-				Assert(CheckRelationLockedByMe(resultRelDesc, RowExclusiveLock, true));
 				InitResultRelInfo(resultRelInfo,
 								  resultRelDesc,
-								  lfirst_int(l),
+								  resultRelIndex,
 								  NULL,
 								  estate->es_instrument);
 				resultRelInfo++;
@@ -967,10 +971,7 @@ InitPlan(QueryDesc *queryDesc, int eflags)
 			case ROW_MARK_SHARE:
 			case ROW_MARK_KEYSHARE:
 			case ROW_MARK_REFERENCE:
-				relation = heap_open(relid, NoLock);
+				relation = ExecGetRangeTableRelation(estate, rc->rti);
-				Assert(CheckRelationLockedByMe(relation,
-											   rt_fetch(rc->rti, rangeTable)->rellockmode,
-											   true));
 				break;
 			case ROW_MARK_COPY:
 				/* no physical table access is required */
@@ -1483,8 +1484,19 @@ ExecCleanUpTriggerState(EState *estate)
 	{
 		ResultRelInfo *resultRelInfo = (ResultRelInfo *) lfirst(l);
 
-		/* Close indices and then the relation itself */
+		/*
-		ExecCloseIndices(resultRelInfo);
+		 * Assert this is a "dummy" ResultRelInfo, see above.  Otherwise we
+		 * might be issuing a duplicate close against a Relation opened by
+		 * ExecGetRangeTableRelation.
+		 */
+		Assert(resultRelInfo->ri_RangeTableIndex == 0);
+
+		/*
+		 * Since ExecGetTriggerResultRel doesn't call ExecOpenIndices for
+		 * these rels, we needn't call ExecCloseIndices either.
+		 */
+		Assert(resultRelInfo->ri_NumIndices == 0);
+
 		heap_close(resultRelInfo->ri_RelationDesc, NoLock);
 	}
 }
@@ -1607,6 +1619,7 @@ static void
 ExecEndPlan(PlanState *planstate, EState *estate)
 {
 	ResultRelInfo *resultRelInfo;
+	int			num_relations;
 	int			i;
 	ListCell   *l;
 
@@ -1634,39 +1647,29 @@ ExecEndPlan(PlanState *planstate, EState *estate)
 	ExecResetTupleTable(estate->es_tupleTable, false);
 
 	/*
-	 * close the result relation(s) if any, but hold locks until xact commit.
+	 * close indexes of result relation(s) if any.  (Rels themselves get
+	 * closed next.)
 	 */
 	resultRelInfo = estate->es_result_relations;
 	for (i = estate->es_num_result_relations; i > 0; i--)
 	{
-		/* Close indices and then the relation itself */
 		ExecCloseIndices(resultRelInfo);
-		heap_close(resultRelInfo->ri_RelationDesc, NoLock);
 		resultRelInfo++;
 	}
 
-	/* Close the root target relation(s). */
+	/*
-	resultRelInfo = estate->es_root_result_relations;
+	 * close whatever rangetable Relations have been opened.  We did not
-	for (i = estate->es_num_root_result_relations; i > 0; i--)
+	 * acquire locks in ExecGetRangeTableRelation, so don't release 'em here.
+	 */
+	num_relations = list_length(estate->es_range_table);
+	for (i = 0; i < num_relations; i++)
 	{
-		heap_close(resultRelInfo->ri_RelationDesc, NoLock);
+		if (estate->es_relations[i])
-		resultRelInfo++;
+			heap_close(estate->es_relations[i], NoLock);
 	}
 
 	/* likewise close any trigger target relations */
 	ExecCleanUpTriggerState(estate);
-
-	/*
-	 * close any relations selected FOR [KEY] UPDATE/SHARE, again keeping
-	 * locks
-	 */
-	foreach(l, estate->es_rowMarks)
-	{
-		ExecRowMark *erm = (ExecRowMark *) lfirst(l);
-
-		if (erm->relation)
-			heap_close(erm->relation, NoLock);
-	}
 }
 
 /* ----------------------------------------------------------------
@@ -3161,6 +3164,7 @@ EvalPlanQualStart(EPQState *epqstate, EState *parentestate, Plan *planTree)
 	estate->es_snapshot = parentestate->es_snapshot;
 	estate->es_crosscheck_snapshot = parentestate->es_crosscheck_snapshot;
 	estate->es_range_table = parentestate->es_range_table;
+	estate->es_relations = parentestate->es_relations;
 	estate->es_plannedstmt = parentestate->es_plannedstmt;
 	estate->es_junkFilter = parentestate->es_junkFilter;
 	estate->es_output_cid = parentestate->es_output_cid;

src/backend/executor/execPartition.c

@@ -219,7 +219,7 @@ ExecFindPartition(ResultRelInfo *resultRelInfo, PartitionDispatch *pd,
 	ExprContext *ecxt = GetPerTupleExprContext(estate);
 	TupleTableSlot *ecxt_scantuple_old = ecxt->ecxt_scantuple;
 	TupleTableSlot *myslot = NULL;
-	MemoryContext	oldcxt;
+	MemoryContext oldcxt;
 
 	/* use per-tuple context here to avoid leaking memory */
 	oldcxt = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
@@ -1389,9 +1389,6 @@ adjust_partition_tlist(List *tlist, TupleConversionMap *map)
  *		functions.  Details stored include how to map the partition index
  *		returned by the partition pruning code into subplan indexes.
  *
- * ExecDestroyPartitionPruneState:
- *		Deletes a PartitionPruneState. Must be called during executor shutdown.
- *
  * ExecFindInitialMatchingSubPlans:
  *		Returns indexes of matching subplans.  Partition pruning is attempted
  *		without any evaluation of expressions containing PARAM_EXEC Params.
@@ -1433,6 +1430,7 @@ PartitionPruneState *
 ExecCreatePartitionPruneState(PlanState *planstate,
 							  PartitionPruneInfo *partitionpruneinfo)
 {
+	EState	   *estate = planstate->state;
 	PartitionPruneState *prunestate;
 	int			n_part_hierarchies;
 	ListCell   *lc;
@@ -1487,6 +1485,7 @@ ExecCreatePartitionPruneState(PlanState *planstate,
 			PartitionedRelPruneInfo *pinfo = lfirst_node(PartitionedRelPruneInfo, lc2);
 			PartitionedRelPruningData *pprune = &prunedata->partrelprunedata[j];
 			PartitionPruneContext *context = &pprune->context;
+			Relation	partrel;
 			PartitionDesc partdesc;
 			PartitionKey partkey;
 			int			partnatts;
@@ -1509,16 +1508,15 @@ ExecCreatePartitionPruneState(PlanState *planstate,
 			pprune->present_parts = bms_copy(pinfo->present_parts);
 
 			/*
-			 * We need to hold a pin on the partitioned table's relcache entry
+			 * We can rely on the copies of the partitioned table's partition
-			 * so that we can rely on its copies of the table's partition key
+			 * key and partition descriptor appearing in its relcache entry,
-			 * and partition descriptor.  We need not get a lock though; one
+			 * because that entry will be held open and locked for the
-			 * should have been acquired already by InitPlan or
+			 * duration of this executor run.
-			 * ExecLockNonLeafAppendTables.
 			 */
-			context->partrel = relation_open(pinfo->reloid, NoLock);
+			partrel = ExecGetRangeTableRelation(estate, pinfo->rtindex);
+			partkey = RelationGetPartitionKey(partrel);
+			partdesc = RelationGetPartitionDesc(partrel);
 
-			partkey = RelationGetPartitionKey(context->partrel);
-			partdesc = RelationGetPartitionDesc(context->partrel);
 			n_steps = list_length(pinfo->pruning_steps);
 
 			context->strategy = partkey->strategy;
@@ -1595,30 +1593,6 @@ ExecCreatePartitionPruneState(PlanState *planstate,
 	return prunestate;
 }
 
-/*
- * ExecDestroyPartitionPruneState
- *		Release resources at plan shutdown.
- *
- * We don't bother to free any memory here, since the whole executor context
- * will be going away shortly.  We do need to release our relcache pins.
- */
-void
-ExecDestroyPartitionPruneState(PartitionPruneState *prunestate)
-{
-	PartitionPruningData **partprunedata = prunestate->partprunedata;
-	int			i;
-
-	for (i = 0; i < prunestate->num_partprunedata; i++)
-	{
-		PartitionPruningData *prunedata = partprunedata[i];
-		PartitionedRelPruningData *pprune = prunedata->partrelprunedata;
-		int			j;
-
-		for (j = 0; j < prunedata->num_partrelprunedata; j++)
-			relation_close(pprune[j].context.partrel, NoLock);
-	}
-}
-
 /*
  * ExecFindInitialMatchingSubPlans
  *		Identify the set of subplans that cannot be eliminated by initial

src/backend/executor/execUtils.c

@@ -25,7 +25,8 @@
  *		etc
  *
  *		ExecOpenScanRelation	Common code for scan node init routines.
- *		ExecCloseScanRelation
+ *
+ *		ExecGetRangeTableRelation		Fetch Relation for a rangetable entry.
  *
  *		executor_errposition	Report syntactic position of an error.
  *
@@ -107,6 +108,7 @@ CreateExecutorState(void)
 	estate->es_snapshot = InvalidSnapshot;	/* caller must initialize this */
 	estate->es_crosscheck_snapshot = InvalidSnapshot;	/* no crosscheck */
 	estate->es_range_table = NIL;
+	estate->es_relations = NULL;
 	estate->es_plannedstmt = NULL;
 
 	estate->es_junkFilter = NULL;
@@ -648,15 +650,9 @@ Relation
 ExecOpenScanRelation(EState *estate, Index scanrelid, int eflags)
 {
 	Relation	rel;
-	Oid			reloid;
 
-	/* Open the relation and verify lock was obtained upstream */
+	/* Open the relation. */
-	reloid = getrelid(scanrelid, estate->es_range_table);
+	rel = ExecGetRangeTableRelation(estate, scanrelid);
-	rel = heap_open(reloid, NoLock);
-	Assert(IsParallelWorker() ||
-		   CheckRelationLockedByMe(rel,
-								   rt_fetch(scanrelid, estate->es_range_table)->rellockmode,
-								   true));
 
 	/*
 	 * Complain if we're attempting a scan of an unscannable relation, except
@@ -674,24 +670,40 @@ ExecOpenScanRelation(EState *estate, Index scanrelid, int eflags)
 	return rel;
 }
 
-/* ----------------------------------------------------------------
+/*
- *		ExecCloseScanRelation
+ * ExecGetRangeTableRelation
+ *		Open the Relation for a range table entry, if not already done
  *
- *		Close the heap relation scanned by a base-level scan plan node.
+ * The Relations will be closed again in ExecEndPlan().
- *		This should be called during the node's ExecEnd routine.
- *
- * Currently, we do not release the lock acquired by ExecOpenScanRelation.
- * This lock should be held till end of transaction.  (There is a faction
- * that considers this too much locking, however.)
- *
- * If we did want to release the lock, we'd have to repeat the logic in
- * ExecOpenScanRelation in order to figure out what to release.
- * ----------------------------------------------------------------
  */
-void
+Relation
-ExecCloseScanRelation(Relation scanrel)
+ExecGetRangeTableRelation(EState *estate, Index rti)
 {
-	heap_close(scanrel, NoLock);
+	Relation	rel;
+
+	Assert(rti > 0 && rti <= list_length(estate->es_range_table));
+
+	rel = estate->es_relations[rti - 1];
+	if (rel == NULL)
+	{
+		/* First time through, so open the relation */
+		RangeTblEntry *rte = rt_fetch(rti, estate->es_range_table);
+
+		Assert(rte->rtekind == RTE_RELATION);
+
+		rel = estate->es_relations[rti - 1] = heap_open(rte->relid, NoLock);
+
+		/*
+		 * Verify that appropriate lock was obtained before execution.
+		 *
+		 * In the case of parallel query, only the leader would've obtained
+		 * the lock (that needs to be fixed, though).
+		 */
+		Assert(IsParallelWorker() ||
+			   CheckRelationLockedByMe(rel, rte->rellockmode, false));
+	}
+
+	return rel;
 }
 
 /*

src/backend/executor/nodeAppend.c

@@ -335,12 +335,6 @@ ExecEndAppend(AppendState *node)
 	 */
 	for (i = 0; i < nplans; i++)
 		ExecEndNode(appendplans[i]);
-
-	/*
-	 * release any resources associated with run-time pruning
-	 */
-	if (node->as_prune_state)
-		ExecDestroyPartitionPruneState(node->as_prune_state);
 }
 
 void

src/backend/executor/nodeBitmapHeapscan.c

@@ -785,13 +785,11 @@ ExecReScanBitmapHeapScan(BitmapHeapScanState *node)
 void
 ExecEndBitmapHeapScan(BitmapHeapScanState *node)
 {
-	Relation	relation;
 	HeapScanDesc scanDesc;
 
 	/*
 	 * extract information from the node
 	 */
-	relation = node->ss.ss_currentRelation;
 	scanDesc = node->ss.ss_currentScanDesc;
 
 	/*
@@ -832,11 +830,6 @@ ExecEndBitmapHeapScan(BitmapHeapScanState *node)
 	 * close heap scan
 	 */
 	heap_endscan(scanDesc);
-
-	/*
-	 * close the heap relation.
-	 */
-	ExecCloseScanRelation(relation);
 }
 
 /* ----------------------------------------------------------------

src/backend/executor/nodeCustom.c

@@ -126,10 +126,6 @@ ExecEndCustomScan(CustomScanState *node)
 	/* Clean out the tuple table */
 	ExecClearTuple(node->ss.ps.ps_ResultTupleSlot);
 	ExecClearTuple(node->ss.ss_ScanTupleSlot);
-
-	/* Close the heap relation */
-	if (node->ss.ss_currentRelation)
-		ExecCloseScanRelation(node->ss.ss_currentRelation);
 }
 
 void

src/backend/executor/nodeForeignscan.c

@@ -258,10 +258,6 @@ ExecEndForeignScan(ForeignScanState *node)
 	/* clean out the tuple table */
 	ExecClearTuple(node->ss.ps.ps_ResultTupleSlot);
 	ExecClearTuple(node->ss.ss_ScanTupleSlot);
-
-	/* close the relation. */
-	if (node->ss.ss_currentRelation)
-		ExecCloseScanRelation(node->ss.ss_currentRelation);
 }
 
 /* ----------------------------------------------------------------

src/backend/executor/nodeIndexonlyscan.c

@@ -373,14 +373,12 @@ ExecEndIndexOnlyScan(IndexOnlyScanState *node)
 {
 	Relation	indexRelationDesc;
 	IndexScanDesc indexScanDesc;
-	Relation	relation;
 
 	/*
 	 * extract information from the node
 	 */
 	indexRelationDesc = node->ioss_RelationDesc;
 	indexScanDesc = node->ioss_ScanDesc;
-	relation = node->ss.ss_currentRelation;
 
 	/* Release VM buffer pin, if any. */
 	if (node->ioss_VMBuffer != InvalidBuffer)
@@ -411,11 +409,6 @@ ExecEndIndexOnlyScan(IndexOnlyScanState *node)
 		index_endscan(indexScanDesc);
 	if (indexRelationDesc)
 		index_close(indexRelationDesc, NoLock);
-
-	/*
-	 * close the heap relation.
-	 */
-	ExecCloseScanRelation(relation);
 }
 
 /* ----------------------------------------------------------------

src/backend/executor/nodeIndexscan.c

@@ -140,7 +140,7 @@ IndexNext(IndexScanState *node)
 		 * Note: we pass 'false' because tuples returned by amgetnext are
 		 * pointers onto disk pages and must not be pfree()'d.
 		 */
-		ExecStoreBufferHeapTuple(tuple,	/* tuple to store */
+		ExecStoreBufferHeapTuple(tuple, /* tuple to store */
 								 slot,	/* slot to store in */
 								 scandesc->xs_cbuf);	/* buffer containing
 														 * tuple */
@@ -285,7 +285,7 @@ next_indextuple:
 		/*
 		 * Store the scanned tuple in the scan tuple slot of the scan state.
 		 */
-		ExecStoreBufferHeapTuple(tuple,	/* tuple to store */
+		ExecStoreBufferHeapTuple(tuple, /* tuple to store */
 								 slot,	/* slot to store in */
 								 scandesc->xs_cbuf);	/* buffer containing
 														 * tuple */
@@ -802,14 +802,12 @@ ExecEndIndexScan(IndexScanState *node)
 {
 	Relation	indexRelationDesc;
 	IndexScanDesc indexScanDesc;
-	Relation	relation;
 
 	/*
 	 * extract information from the node
 	 */
 	indexRelationDesc = node->iss_RelationDesc;
 	indexScanDesc = node->iss_ScanDesc;
-	relation = node->ss.ss_currentRelation;
 
 	/*
 	 * Free the exprcontext(s) ... now dead code, see ExecFreeExprContext
@@ -833,11 +831,6 @@ ExecEndIndexScan(IndexScanState *node)
 		index_endscan(indexScanDesc);
 	if (indexRelationDesc)
 		index_close(indexRelationDesc, NoLock);
-
-	/*
-	 * close the heap relation.
-	 */
-	ExecCloseScanRelation(relation);
 }
 
 /* ----------------------------------------------------------------

src/backend/executor/nodeMergeAppend.c

@@ -369,12 +369,6 @@ ExecEndMergeAppend(MergeAppendState *node)
 	 */
 	for (i = 0; i < nplans; i++)
 		ExecEndNode(mergeplans[i]);
-
-	/*
-	 * release any resources associated with run-time pruning
-	 */
-	if (node->ms_prune_state)
-		ExecDestroyPartitionPruneState(node->ms_prune_state);
 }
 
 void

src/backend/executor/nodeSamplescan.c

@@ -63,9 +63,9 @@ SampleNext(SampleScanState *node)
 	slot = node->ss.ss_ScanTupleSlot;
 
 	if (tuple)
-		ExecStoreBufferHeapTuple(tuple,	/* tuple to store */
+		ExecStoreBufferHeapTuple(tuple, /* tuple to store */
 								 slot,	/* slot to store in */
-								 node->ss.ss_currentScanDesc->rs_cbuf);	/* tuple's buffer */
+								 node->ss.ss_currentScanDesc->rs_cbuf); /* tuple's buffer */
 	else
 		ExecClearTuple(slot);
 
@@ -222,11 +222,6 @@ ExecEndSampleScan(SampleScanState *node)
 	 */
 	if (node->ss.ss_currentScanDesc)
 		heap_endscan(node->ss.ss_currentScanDesc);
-
-	/*
-	 * close the heap relation.
-	 */
-	ExecCloseScanRelation(node->ss.ss_currentRelation);
 }
 
 /* ----------------------------------------------------------------

src/backend/executor/nodeSeqscan.c

@@ -88,7 +88,7 @@ SeqNext(SeqScanState *node)
 	 * refcount will not be dropped until the tuple table slot is cleared.
 	 */
 	if (tuple)
-		ExecStoreBufferHeapTuple(tuple,	/* tuple to store */
+		ExecStoreBufferHeapTuple(tuple, /* tuple to store */
 								 slot,	/* slot to store in */
 								 scandesc->rs_cbuf);	/* buffer associated
 														 * with this tuple */
@@ -201,13 +201,11 @@ ExecInitSeqScan(SeqScan *node, EState *estate, int eflags)
 void
 ExecEndSeqScan(SeqScanState *node)
 {
-	Relation	relation;
 	HeapScanDesc scanDesc;
 
 	/*
 	 * get information from node
 	 */
-	relation = node->ss.ss_currentRelation;
 	scanDesc = node->ss.ss_currentScanDesc;
 
 	/*
@@ -226,11 +224,6 @@ ExecEndSeqScan(SeqScanState *node)
 	 */
 	if (scanDesc != NULL)
 		heap_endscan(scanDesc);
-
-	/*
-	 * close the heap relation.
-	 */
-	ExecCloseScanRelation(relation);
 }
 
 /* ----------------------------------------------------------------

src/backend/executor/nodeTidscan.c

@@ -380,7 +380,7 @@ TidNext(TidScanState *node)
 			 * Store the scanned tuple in the scan tuple slot of the scan
 			 * state.  Eventually we will only do this and not return a tuple.
 			 */
-			ExecStoreBufferHeapTuple(tuple,	/* tuple to store */
+			ExecStoreBufferHeapTuple(tuple, /* tuple to store */
 									 slot,	/* slot to store in */
 									 buffer);	/* buffer associated with
 												 * tuple */
@@ -489,11 +489,6 @@ ExecEndTidScan(TidScanState *node)
 	 */
 	ExecClearTuple(node->ss.ps.ps_ResultTupleSlot);
 	ExecClearTuple(node->ss.ss_ScanTupleSlot);
-
-	/*
-	 * close the heap relation.
-	 */
-	ExecCloseScanRelation(node->ss.ss_currentRelation);
 }
 
 /* ----------------------------------------------------------------

src/backend/nodes/copyfuncs.c

@@ -1193,7 +1193,7 @@ _copyPartitionedRelPruneInfo(const PartitionedRelPruneInfo *from)
 {
 	PartitionedRelPruneInfo *newnode = makeNode(PartitionedRelPruneInfo);
 
-	COPY_SCALAR_FIELD(reloid);
+	COPY_SCALAR_FIELD(rtindex);
 	COPY_NODE_FIELD(pruning_steps);
 	COPY_BITMAPSET_FIELD(present_parts);
 	COPY_SCALAR_FIELD(nparts);

src/backend/nodes/outfuncs.c

@@ -1032,7 +1032,7 @@ _outPartitionedRelPruneInfo(StringInfo str, const PartitionedRelPruneInfo *node)
 
 	WRITE_NODE_TYPE("PARTITIONEDRELPRUNEINFO");
 
-	WRITE_OID_FIELD(reloid);
+	WRITE_UINT_FIELD(rtindex);
 	WRITE_NODE_FIELD(pruning_steps);
 	WRITE_BITMAPSET_FIELD(present_parts);
 	WRITE_INT_FIELD(nparts);

src/backend/nodes/readfuncs.c

@@ -2376,7 +2376,7 @@ _readPartitionedRelPruneInfo(void)
 {
 	READ_LOCALS(PartitionedRelPruneInfo);
 
-	READ_OID_FIELD(reloid);
+	READ_UINT_FIELD(rtindex);
 	READ_NODE_FIELD(pruning_steps);
 	READ_BITMAPSET_FIELD(present_parts);
 	READ_INT_FIELD(nparts);

src/backend/optimizer/plan/setrefs.c

@@ -925,6 +925,21 @@ set_plan_refs(PlannerInfo *root, Plan *plan, int rtoffset)
 											  (Plan *) lfirst(l),
 											  rtoffset);
 				}
+				if (splan->part_prune_info)
+				{
+					foreach(l, splan->part_prune_info->prune_infos)
+					{
+						List	   *prune_infos = lfirst(l);
+						ListCell   *l2;
+
+						foreach(l2, prune_infos)
+						{
+							PartitionedRelPruneInfo *pinfo = lfirst(l2);
+
+							pinfo->rtindex += rtoffset;
+						}
+					}
+				}
 			}
 			break;
 		case T_MergeAppend:
@@ -947,6 +962,21 @@ set_plan_refs(PlannerInfo *root, Plan *plan, int rtoffset)
 											  (Plan *) lfirst(l),
 											  rtoffset);
 				}
+				if (splan->part_prune_info)
+				{
+					foreach(l, splan->part_prune_info->prune_infos)
+					{
+						List	   *prune_infos = lfirst(l);
+						ListCell   *l2;
+
+						foreach(l2, prune_infos)
+						{
+							PartitionedRelPruneInfo *pinfo = lfirst(l2);
+
+							pinfo->rtindex += rtoffset;
+						}
+					}
+				}
 			}
 			break;
 		case T_RecursiveUnion:

src/backend/partitioning/partprune.c

@@ -357,7 +357,6 @@ make_partitionedrel_pruneinfo(PlannerInfo *root, RelOptInfo *parentrel,
 		Index		rti = lfirst_int(lc);
 		RelOptInfo *subpart = find_base_rel(root, rti);
 		PartitionedRelPruneInfo *pinfo;
-		RangeTblEntry *rte;
 		Bitmapset  *present_parts;
 		int			nparts = subpart->nparts;
 		int			partnatts = subpart->part_scheme->partnatts;
@@ -459,10 +458,8 @@ make_partitionedrel_pruneinfo(PlannerInfo *root, RelOptInfo *parentrel,
 				present_parts = bms_add_member(present_parts, i);
 		}
 
-		rte = root->simple_rte_array[subpart->relid];
-
 		pinfo = makeNode(PartitionedRelPruneInfo);
-		pinfo->reloid = rte->relid;
+		pinfo->rtindex = rti;
 		pinfo->pruning_steps = pruning_steps;
 		pinfo->present_parts = present_parts;
 		pinfo->nparts = nparts;
@@ -587,7 +584,6 @@ prune_append_rel_partitions(RelOptInfo *rel)
 	context.ppccontext = CurrentMemoryContext;
 
 	/* These are not valid when being called from the planner */
-	context.partrel = NULL;
 	context.planstate = NULL;
 	context.exprstates = NULL;
 	context.exprhasexecparam = NULL;

src/backend/replication/logical/worker.c

@@ -201,6 +201,7 @@ create_estate_for_relation(LogicalRepRelMapEntry *rel)
 	rte->relkind = rel->localrel->rd_rel->relkind;
 	rte->rellockmode = AccessShareLock;
 	estate->es_range_table = list_make1(rte);
+	estate->es_relations = (Relation *) palloc0(1 * sizeof(Relation));
 
 	resultRelInfo = makeNode(ResultRelInfo);
 	InitResultRelInfo(resultRelInfo, rel->localrel, 1, NULL, 0);

src/include/executor/execPartition.h

@@ -195,7 +195,6 @@ extern void ExecCleanupTupleRouting(ModifyTableState *mtstate,
 						PartitionTupleRouting *proute);
 extern PartitionPruneState *ExecCreatePartitionPruneState(PlanState *planstate,
 							  PartitionPruneInfo *partitionpruneinfo);
-extern void ExecDestroyPartitionPruneState(PartitionPruneState *prunestate);
 extern Bitmapset *ExecFindMatchingSubPlans(PartitionPruneState *prunestate);
 extern Bitmapset *ExecFindInitialMatchingSubPlans(PartitionPruneState *prunestate,
 								int nsubplans);

src/include/executor/executor.h

@@ -513,7 +513,8 @@ extern void ExecCreateScanSlotFromOuterPlan(EState *estate, ScanState *scanstate
 extern bool ExecRelationIsTargetRelation(EState *estate, Index scanrelid);
 
 extern Relation ExecOpenScanRelation(EState *estate, Index scanrelid, int eflags);
-extern void ExecCloseScanRelation(Relation scanrel);
+
+extern Relation ExecGetRangeTableRelation(EState *estate, Index rti);
 
 extern int	executor_errposition(EState *estate, int location);
 

src/include/nodes/execnodes.h

@@ -386,12 +386,19 @@ typedef struct OnConflictSetState
  * Whenever we update an existing relation, we have to update indexes on the
  * relation, and perhaps also fire triggers.  ResultRelInfo holds all the
  * information needed about a result relation, including indexes.
+ *
+ * Normally, a ResultRelInfo refers to a table that is in the query's
+ * range table; then ri_RangeTableIndex is the RT index and ri_RelationDesc
+ * is just a copy of the relevant es_relations[] entry.  But sometimes,
+ * in ResultRelInfos used only for triggers, ri_RangeTableIndex is zero
+ * and ri_RelationDesc is a separately-opened relcache pointer that needs
+ * to be separately closed.  See ExecGetTriggerResultRel.
  */
 typedef struct ResultRelInfo
 {
 	NodeTag		type;
 
-	/* result relation's range table index */
+	/* result relation's range table index, or 0 if not in range table */
 	Index		ri_RangeTableIndex;
 
 	/* relation descriptor for result relation */
@@ -479,6 +486,8 @@ typedef struct EState
 	Snapshot	es_snapshot;	/* time qual to use */
 	Snapshot	es_crosscheck_snapshot; /* crosscheck time qual for RI */
 	List	   *es_range_table; /* List of RangeTblEntry */
+	Relation   *es_relations;	/* Array of per-es_range_table-entry Relation
+								 * pointers, or NULL if not yet opened */
 	PlannedStmt *es_plannedstmt;	/* link to top of plan tree */
 	const char *es_sourceText;	/* Source text from QueryDesc */
 

src/include/nodes/plannodes.h

@@ -1105,7 +1105,7 @@ typedef struct PartitionPruneInfo
 typedef struct PartitionedRelPruneInfo
 {
 	NodeTag		type;
-	Oid			reloid;			/* OID of partition rel for this level */
+	Index		rtindex;		/* RT index of partition rel for this level */
 	List	   *pruning_steps;	/* List of PartitionPruneStep, see below */
 	Bitmapset  *present_parts;	/* Indexes of all partitions which subplans or
 								 * subparts are present for. */

src/include/partitioning/partprune.h

@@ -23,8 +23,6 @@
  *		Stores information needed at runtime for pruning computations
  *		related to a single partitioned table.
  *
- * partrel			Relcache pointer for the partitioned table,
- *					if we have it open (else NULL).
  * strategy			Partition strategy, e.g. LIST, RANGE, HASH.
  * partnatts		Number of columns in the partition key.
  * nparts			Number of partitions in this partitioned table.
@@ -50,7 +48,6 @@
  */
 typedef struct PartitionPruneContext
 {
-	Relation	partrel;
 	char		strategy;
 	int			partnatts;
 	int			nparts;