diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c
index 97091dd..d4ac2e1 100644
--- a/src/backend/commands/indexcmds.c
+++ b/src/backend/commands/indexcmds.c
@@ -861,6 +861,7 @@ DefineIndex(Oid relationId,
 
 	PopActiveSnapshot();
 	UnregisterSnapshot(snapshot);
+	InvalidateCatalogSnapshotConditionally();
 
 	/*
 	 * The index is now valid in the sense that it contains all currently