1 files changed, 6 insertions, 0 deletions
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c
index 4cb1744da6..c334daae39 100644
--- a/src/backend/nodes/nodeFuncs.c
+++ b/src/backend/nodes/nodeFuncs.c
@@ -760,6 +760,12 @@ expression_returns_set_walker(Node *node, void *context)
 		/* else fall through to check args */
 	}
 
+	/*
+	 * If you add any more cases that return sets, also fix
+	 * expression_returns_set_rows() in clauses.c and IS_SRF_CALL() in
+	 * tlist.c.
+	 */
+
 	/* Avoid recursion for some cases that parser checks not to return a set */
 	if (IsA(node, Aggref))
 		return false;