8 files changed, 32 insertions, 86 deletions

diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c
index 8d1d0aa927d..e1b280a065c 100644
--- a/src/backend/executor/execMain.c
+++ b/src/backend/executor/execMain.c
@@ -85,7 +85,6 @@ static char *ExecBuildSlotValueDescription(TupleTableSlot *slot,
 							  int maxfieldlen);
 static void EvalPlanQualStart(EPQState *epqstate, EState *parentestate,
 				  Plan *planTree);
-static bool RelationIdIsScannable(Oid relid);
 
 /* end of local decls */
 
@@ -495,63 +494,6 @@ ExecutorRewind(QueryDesc *queryDesc)
 
 
 /*
- * ExecCheckRelationsScannable
- *		Check that relations which are to be accessed are in a scannable
- *		state.
- *
- * Currently the only relations which are not are materialized views which
- * have not been populated by their queries.
- */
-static void
-ExecCheckRelationsScannable(List *rangeTable)
-{
-	ListCell   *l;
-
-	foreach(l, rangeTable)
-	{
-		RangeTblEntry *rte = (RangeTblEntry *) lfirst(l);
-
-		if (rte->rtekind != RTE_RELATION)
-			continue;
-
-		if (rte->relkind != RELKIND_MATVIEW)
-			continue;
-
-		/* It is OK to target an unpopulated materialized for results. */
-		if (rte->isResultRel)
-			continue;
-
-		if (!RelationIdIsScannable(rte->relid))
-			ereport(ERROR,
-					(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-					 errmsg("materialized view \"%s\" has not been populated",
-							get_rel_name(rte->relid)),
-					 errhint("Use the REFRESH MATERIALIZED VIEW command.")));
-	}
-}
-
-/*
- * Tells whether a relation is scannable based on its OID.
- *
- * Currently only non-populated materialized views are not.  This is likely to
- * change to include other conditions.
- *
- * This should only be called while a lock is held on the relation.
- */
-static bool
-RelationIdIsScannable(Oid relid)
-{
-	Relation	relation;
-	bool		result;
-
-	relation = heap_open(relid, NoLock);
-	result = RelationIsScannable(relation);
-	heap_close(relation, NoLock);
-
-	return result;
-}
-
-/*
  * ExecCheckRTPerms
  *		Check access permissions for all relations listed in a range table.
  *
@@ -942,20 +884,6 @@ InitPlan(QueryDesc *queryDesc, int eflags)
 	planstate = ExecInitNode(plan, estate, eflags);
 
 	/*
-	 * Unless we are creating a view or are creating a materialized view WITH
-	 * NO DATA, ensure that all referenced relations are scannable.  The
-	 * omitted cases will be checked as SELECT statements in a different
-	 * phase, so checking again here would be wasteful and it would generate
-	 * errors on a materialized view referenced as a target.
-	 *
-	 * NB: This is being done after all relations are locked, files have been
-	 * opened, etc., to avoid duplicating that effort or creating deadlock
-	 * possibilities.
-	 */
-	if ((eflags & EXEC_FLAG_WITH_NO_DATA) == 0)
-		ExecCheckRelationsScannable(rangeTable);
-
-	/*
 	 * Get the tuple descriptor describing the type of tuples to return.
 	 */
 	tupType = ExecGetResultType(planstate);
diff --git a/src/backend/executor/execUtils.c b/src/backend/executor/execUtils.c
index 11be62e9153..cf7fb72ffcf 100644
--- a/src/backend/executor/execUtils.c
+++ b/src/backend/executor/execUtils.c
@@ -798,8 +798,9 @@ ExecRelationIsTargetRelation(EState *estate, Index scanrelid)
  * ----------------------------------------------------------------
  */
 Relation
-ExecOpenScanRelation(EState *estate, Index scanrelid)
+ExecOpenScanRelation(EState *estate, Index scanrelid, int eflags)
 {
+	Relation	rel;
 	Oid			reloid;
 	LOCKMODE	lockmode;
 
@@ -827,9 +828,24 @@ ExecOpenScanRelation(EState *estate, Index scanrelid)
 		}
 	}
 
-	/* OK, open the relation and acquire lock as needed */
+	/* Open the relation and acquire lock as needed */
 	reloid = getrelid(scanrelid, estate->es_range_table);
-	return heap_open(reloid, lockmode);
+	rel = heap_open(reloid, lockmode);
+
+	/*
+	 * Complain if we're attempting a scan of an unscannable relation, except
+	 * when the query won't actually be run.  This is a slightly klugy place
+	 * to do this, perhaps, but there is no better place.
+	 */
+	if ((eflags & (EXEC_FLAG_EXPLAIN_ONLY | EXEC_FLAG_WITH_NO_DATA)) == 0 &&
+		!RelationIsScannable(rel))
+		ereport(ERROR,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("materialized view \"%s\" has not been populated",
+						RelationGetRelationName(rel)),
+				 errhint("Use the REFRESH MATERIALIZED VIEW command.")));
+
+	return rel;
 }
 
 /* ----------------------------------------------------------------
diff --git a/src/backend/executor/nodeBitmapHeapscan.c b/src/backend/executor/nodeBitmapHeapscan.c
index c83f9722cf9..d2b27213ffe 100644
--- a/src/backend/executor/nodeBitmapHeapscan.c
+++ b/src/backend/executor/nodeBitmapHeapscan.c
@@ -587,7 +587,7 @@ ExecInitBitmapHeapScan(BitmapHeapScan *node, EState *estate, int eflags)
 	/*
 	 * open the base relation and acquire appropriate lock on it.
 	 */
-	currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid);
+	currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid, eflags);
 
 	scanstate->ss.ss_currentRelation = currentRelation;
 
diff --git a/src/backend/executor/nodeForeignscan.c b/src/backend/executor/nodeForeignscan.c
index 448fd6a912f..c0b3525e50d 100644
--- a/src/backend/executor/nodeForeignscan.c
+++ b/src/backend/executor/nodeForeignscan.c
@@ -143,7 +143,7 @@ ExecInitForeignScan(ForeignScan *node, EState *estate, int eflags)
 	/*
 	 * open the base relation and acquire appropriate lock on it.
 	 */
-	currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid);
+	currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid, eflags);
 	scanstate->ss.ss_currentRelation = currentRelation;
 
 	/*
diff --git a/src/backend/executor/nodeIndexonlyscan.c b/src/backend/executor/nodeIndexonlyscan.c
index 7d01f8166e6..2f30c55c54a 100644
--- a/src/backend/executor/nodeIndexonlyscan.c
+++ b/src/backend/executor/nodeIndexonlyscan.c
@@ -410,7 +410,7 @@ ExecInitIndexOnlyScan(IndexOnlyScan *node, EState *estate, int eflags)
 	/*
 	 * open the base relation and acquire appropriate lock on it.
 	 */
-	currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid);
+	currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid, eflags);
 
 	indexstate->ss.ss_currentRelation = currentRelation;
 	indexstate->ss.ss_currentScanDesc = NULL;	/* no heap scan here */
diff --git a/src/backend/executor/nodeIndexscan.c b/src/backend/executor/nodeIndexscan.c
index c71a382af81..f1062f19f43 100644
--- a/src/backend/executor/nodeIndexscan.c
+++ b/src/backend/executor/nodeIndexscan.c
@@ -511,7 +511,7 @@ ExecInitIndexScan(IndexScan *node, EState *estate, int eflags)
 	/*
 	 * open the base relation and acquire appropriate lock on it.
 	 */
-	currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid);
+	currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid, eflags);
 
 	indexstate->ss.ss_currentRelation = currentRelation;
 	indexstate->ss.ss_currentScanDesc = NULL;	/* no heap scan here */
diff --git a/src/backend/executor/nodeSeqscan.c b/src/backend/executor/nodeSeqscan.c
index c6f2eabedee..c4edec0750b 100644
--- a/src/backend/executor/nodeSeqscan.c
+++ b/src/backend/executor/nodeSeqscan.c
@@ -29,7 +29,7 @@
 #include "executor/nodeSeqscan.h"
 #include "utils/rel.h"
 
-static void InitScanRelation(SeqScanState *node, EState *estate);
+static void InitScanRelation(SeqScanState *node, EState *estate, int eflags);
 static TupleTableSlot *SeqNext(SeqScanState *node);
 
 /* ----------------------------------------------------------------
@@ -118,12 +118,11 @@ ExecSeqScan(SeqScanState *node)
 /* ----------------------------------------------------------------
  *		InitScanRelation
  *
- *		This does the initialization for scan relations and
- *		subplans of scans.
+ *		Set up to access the scan relation.
  * ----------------------------------------------------------------
  */
 static void
-InitScanRelation(SeqScanState *node, EState *estate)
+InitScanRelation(SeqScanState *node, EState *estate, int eflags)
 {
 	Relation	currentRelation;
 	HeapScanDesc currentScanDesc;
@@ -133,8 +132,10 @@ InitScanRelation(SeqScanState *node, EState *estate)
 	 * open that relation and acquire appropriate lock on it.
 	 */
 	currentRelation = ExecOpenScanRelation(estate,
-									 ((SeqScan *) node->ps.plan)->scanrelid);
+									 ((SeqScan *) node->ps.plan)->scanrelid,
+										   eflags);
 
+	/* initialize a heapscan */
 	currentScanDesc = heap_beginscan(currentRelation,
 									 estate->es_snapshot,
 									 0,
@@ -143,6 +144,7 @@ InitScanRelation(SeqScanState *node, EState *estate)
 	node->ss_currentRelation = currentRelation;
 	node->ss_currentScanDesc = currentScanDesc;
 
+	/* and report the scan tuple slot's rowtype */
 	ExecAssignScanType(node, RelationGetDescr(currentRelation));
 }
 
@@ -196,7 +198,7 @@ ExecInitSeqScan(SeqScan *node, EState *estate, int eflags)
 	/*
 	 * initialize scan relation
 	 */
-	InitScanRelation(scanstate, estate);
+	InitScanRelation(scanstate, estate, eflags);
 
 	scanstate->ps.ps_TupFromTlist = false;
 
diff --git a/src/backend/executor/nodeTidscan.c b/src/backend/executor/nodeTidscan.c
index ced9c8b1b58..316a4ed0136 100644
--- a/src/backend/executor/nodeTidscan.c
+++ b/src/backend/executor/nodeTidscan.c
@@ -531,7 +531,7 @@ ExecInitTidScan(TidScan *node, EState *estate, int eflags)
 	/*
 	 * open the base relation and acquire appropriate lock on it.
 	 */
-	currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid);
+	currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid, eflags);
 
 	tidstate->ss.ss_currentRelation = currentRelation;
 	tidstate->ss.ss_currentScanDesc = NULL;		/* no heap scan here */