diff --git a/src/test/regress/expected/union.out b/src/test/regress/expected/union.out
index 73e320bad47..882017afc9a 100644
--- a/src/test/regress/expected/union.out
+++ b/src/test/regress/expected/union.out
@@ -1438,7 +1438,7 @@ where (x = 0) or (q1 >= q2 and q1 <= q2);
 -- Ensure we get a Nested Loop join between tenk1 and tenk2
 explain (costs off)
 select t1.unique1 from tenk1 t1
-inner join tenk2 t2 on t1.tenthous = t2.tenthous
+inner join tenk2 t2 on t1.tenthous = t2.tenthous and t2.thousand = 0
    union all
 (values(1)) limit 1;
                        QUERY PLAN                       
@@ -1450,8 +1450,9 @@ inner join tenk2 t2 on t1.tenthous = t2.tenthous
                ->  Seq Scan on tenk1 t1
                ->  Materialize
                      ->  Seq Scan on tenk2 t2
+                           Filter: (thousand = 0)
          ->  Result
-(8 rows)
+(9 rows)
 
 -- Ensure there is no problem if cheapest_startup_path is NULL
 explain (costs off)
diff --git a/src/test/regress/sql/union.sql b/src/test/regress/sql/union.sql
index 6c509ac80cb..d160db54588 100644
--- a/src/test/regress/sql/union.sql
+++ b/src/test/regress/sql/union.sql
@@ -548,7 +548,7 @@ where (x = 0) or (q1 >= q2 and q1 <= q2);
 -- Ensure we get a Nested Loop join between tenk1 and tenk2
 explain (costs off)
 select t1.unique1 from tenk1 t1
-inner join tenk2 t2 on t1.tenthous = t2.tenthous
+inner join tenk2 t2 on t1.tenthous = t2.tenthous and t2.thousand = 0
    union all
 (values(1)) limit 1;