Avoid failure to open dropped detached partition

alvherre · alvherre · commit 52f3de874bbe · 2024-08-19T16:09:10.000-04:00
When a partition is detached and immediately dropped, a prepared statement could try to compute a new partition descriptor that includes it. This leads to this kind of error: ERROR: could not open relation with OID 457639 Avoid this by skipping the partition in expand_partitioned_rtentry if it doesn't exist. Noted by me while investigating bug #18559. Kuntal Gosh helped to identify the exact failure. Backpatch to 14, where DETACH CONCURRENTLY was introduced. Author: Álvaro Herrera <alvherre@alvh.no-ip.org> Reviewed-by: Kuntal Ghosh <kuntalghosh.2007@gmail.com> Reviewed-by: Junwang Zhao <zhjwpku@gmail.com> Discussion: https://postgr.es/m/202408122233.bo4adt3vh5bi@alvherre.pgsql
diff --git a/src/backend/optimizer/util/inherit.c b/src/backend/optimizer/util/inherit.c
@@ -386,8 +386,17 @@ expand_partitioned_rtentry(PlannerInfo *root, RelOptInfo *relinfo,
 		Index		childRTindex;
 		RelOptInfo *childrelinfo;
 
-		/* Open rel, acquiring required locks */
-		childrel = table_open(childOID, lockmode);
+		/*
+		 * Open rel, acquiring required locks.  If a partition was recently
+		 * detached and subsequently dropped, then opening it will fail.  In
+		 * this case, behave as though the partition had been pruned.
+		 */
+		childrel = try_table_open(childOID, lockmode);
+		if (childrel == NULL)
+		{
+			relinfo->live_parts = bms_del_member(relinfo->live_parts, i);
+			continue;
+		}
 
 		/*
 		 * Temporary partitions belonging to other sessions should have been
