diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c
index ca24620fd0..d35deb433a 100644
--- a/src/backend/commands/indexcmds.c
+++ b/src/backend/commands/indexcmds.c
@@ -1163,15 +1163,17 @@ DefineIndex(Oid relationId,
 
 	if (partitioned)
 	{
+		PartitionDesc partdesc;
+
 		/*
 		 * Unless caller specified to skip this step (via ONLY), process each
 		 * partition to make sure they all contain a corresponding index.
 		 *
 		 * If we're called internally (no stmt->relation), recurse always.
 		 */
-		if (!stmt->relation || stmt->relation->inh)
+		partdesc = RelationGetPartitionDesc(rel);
+		if ((!stmt->relation || stmt->relation->inh) && partdesc->nparts > 0)
 		{
-			PartitionDesc partdesc = RelationGetPartitionDesc(rel);
 			int			nparts = partdesc->nparts;
 			Oid		   *part_oids = palloc(sizeof(Oid) * nparts);
 			bool		invalidate_parent = false;