Diagnose !indisvalid in more SQL functions.

pgstatindex failed with ERRCODE_DATA_CORRUPTED, of the "can't-happen"
class XX.  The other functions succeeded on an empty index; they might
have malfunctioned if the failed index build left torn I/O or other
complex state.  Report an ERROR in statistics functions pgstatindex,
pgstatginindex, pgstathashindex, and pgstattuple.  Report DEBUG1 and
skip all index I/O in maintenance functions brin_desummarize_range,
brin_summarize_new_values, brin_summarize_range, and
gin_clean_pending_list.  Back-patch to v11 (all supported versions).

Discussion: https://postgr.es/m/20231001195309.a3@google.com

2 files changed, 41 insertions, 9 deletions

diff --git a/src/backend/access/brin/brin.c b/src/backend/access/brin/brin.c
index eb318303c7d..81f819ecc45 100644
--- a/src/backend/access/brin/brin.c
+++ b/src/backend/access/brin/brin.c
@@ -1039,8 +1039,14 @@ brin_summarize_range(PG_FUNCTION_ARGS)
 				 errmsg("could not open parent table of index %s",
 						RelationGetRelationName(indexRel))));
 
-	/* OK, do it */
-	brinsummarize(indexRel, heapRel, heapBlk, true, &numSummarized, NULL);
+	/* see gin_clean_pending_list() */
+	if (indexRel->rd_index->indisvalid)
+		brinsummarize(indexRel, heapRel, heapBlk, true, &numSummarized, NULL);
+	else
+		ereport(DEBUG1,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("index \"%s\" is not valid",
+						RelationGetRelationName(indexRel))));
 
 	/* Roll back any GUC changes executed by index functions */
 	AtEOXact_GUC(false, save_nestlevel);
@@ -1125,12 +1131,21 @@ brin_desummarize_range(PG_FUNCTION_ARGS)
 				 errmsg("could not open parent table of index %s",
 						RelationGetRelationName(indexRel))));
 
-	/* the revmap does the hard work */
-	do
+	/* see gin_clean_pending_list() */
+	if (indexRel->rd_index->indisvalid)
 	{
-		done = brinRevmapDesummarizeRange(indexRel, heapBlk);
+		/* the revmap does the hard work */
+		do
+		{
+			done = brinRevmapDesummarizeRange(indexRel, heapBlk);
+		}
+		while (!done);
 	}
-	while (!done);
+	else
+		ereport(DEBUG1,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("index \"%s\" is not valid",
+						RelationGetRelationName(indexRel))));
 
 	relation_close(indexRel, ShareUpdateExclusiveLock);
 	relation_close(heapRel, ShareUpdateExclusiveLock);
diff --git a/src/backend/access/gin/ginfast.c b/src/backend/access/gin/ginfast.c
index 4dcfdf2ac63..39eb9e14cd4 100644
--- a/src/backend/access/gin/ginfast.c
+++ b/src/backend/access/gin/ginfast.c
@@ -1041,7 +1041,6 @@ gin_clean_pending_list(PG_FUNCTION_ARGS)
 	Oid			indexoid = PG_GETARG_OID(0);
 	Relation	indexRel = index_open(indexoid, RowExclusiveLock);
 	IndexBulkDeleteResult stats;
-	GinState	ginstate;
 
 	if (RecoveryInProgress())
 		ereport(ERROR,
@@ -1073,8 +1072,26 @@ gin_clean_pending_list(PG_FUNCTION_ARGS)
 					   RelationGetRelationName(indexRel));
 
 	memset(&stats, 0, sizeof(stats));
-	initGinState(&ginstate, indexRel);
-	ginInsertCleanup(&ginstate, true, true, true, &stats);
+
+	/*
+	 * Can't assume anything about the content of an !indisready index.  Make
+	 * those a no-op, not an error, so users can just run this function on all
+	 * indexes of the access method.  Since an indisready&&!indisvalid index
+	 * is merely awaiting missed aminsert calls, we're capable of processing
+	 * it.  Decline to do so, out of an abundance of caution.
+	 */
+	if (indexRel->rd_index->indisvalid)
+	{
+		GinState	ginstate;
+
+		initGinState(&ginstate, indexRel);
+		ginInsertCleanup(&ginstate, true, true, true, &stats);
+	}
+	else
+		ereport(DEBUG1,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("index \"%s\" is not valid",
+						RelationGetRelationName(indexRel))));
 
 	index_close(indexRel, RowExclusiveLock);