diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql
index 1824cb67fe9..c6f613019c3 100644
--- a/contrib/postgres_fdw/sql/postgres_fdw.sql
+++ b/contrib/postgres_fdw/sql/postgres_fdw.sql
@@ -3025,6 +3025,22 @@ EXPLAIN (VERBOSE, COSTS OFF)
 SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ORDER BY 1;
 SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 ORDER BY 1;
 
+CREATE FUNCTION f() RETURNS INT AS $$
+begin
+  return 10;
+end 
+$$ LANGUAGE PLPGSQL;
+
+EXPLAIN (VERBOSE, COSTS OFF)
+SELECT b, sum(a) FROM pagg_tab GROUP BY b HAVING sum(a) < f() ORDER BY 1;
+SELECT b, sum(a) FROM pagg_tab GROUP BY b HAVING sum(a) < f() ORDER BY 1;
+
+EXPLAIN (VERBOSE, COSTS OFF)
+SELECT b, sum(a) FROM pagg_tab GROUP BY b ORDER BY 1;
+SELECT b, sum(a) FROM pagg_tab GROUP BY b ORDER BY 1;
+
+DROP function f();
+
 -- Partial aggregates are safe to push down without having clause
 EXPLAIN (VERBOSE, COSTS OFF)
 SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b ORDER BY 1;