diff --git a/src/test/regress/expected/partition_prune.out b/src/test/regress/expected/partition_prune.out
index 693c348185..61457862a9 100644
--- a/src/test/regress/expected/partition_prune.out
+++ b/src/test/regress/expected/partition_prune.out
@@ -2478,6 +2478,8 @@ deallocate ab_q3;
 deallocate ab_q4;
 deallocate ab_q5;
 -- UPDATE on a partition subtree has been seen to have problems.
+set enable_hashjoin to off;
+set enable_mergejoin to off;
 insert into ab values (1,2);
 explain (analyze, costs off, summary off, timing off)
 update ab_a1 set b = 3 from ab where ab.a = 1 and ab.a = ab_a1.a;
@@ -2556,6 +2558,69 @@ table ab;
  1 | 3
 (1 row)
 
+truncate ab;
+insert into ab values (1, 1), (1, 2), (1, 3);
+explain (analyze, costs off, summary off, timing off)
+update ab_a1 set b = 3 from (select * from (select * from ab_a2 union all select 1, 2) s where s.b = (select 2)) ss where ss.a = ab_a1.a;
+                                   QUERY PLAN                                    
+---------------------------------------------------------------------------------
+ Update on ab_a1 (actual rows=0 loops=1)
+   Update on ab_a1_b1
+   Update on ab_a1_b2
+   Update on ab_a1_b3
+   InitPlan 1 (returns $0)
+     ->  Result (actual rows=1 loops=1)
+   ->  Nested Loop (actual rows=1 loops=1)
+         ->  Append (actual rows=1 loops=1)
+               ->  Seq Scan on ab_a2_b1 (never executed)
+                     Filter: (b = $0)
+               ->  Seq Scan on ab_a2_b2 (actual rows=0 loops=1)
+                     Filter: (b = $0)
+               ->  Seq Scan on ab_a2_b3 (never executed)
+                     Filter: (b = $0)
+               ->  Subquery Scan on "*SELECT* 2" (actual rows=1 loops=1)
+                     ->  Result (actual rows=1 loops=1)
+                           One-Time Filter: (2 = $0)
+         ->  Index Scan using ab_a1_b1_a_idx on ab_a1_b1 (actual rows=1 loops=1)
+               Index Cond: (a = ab_a2_b1.a)
+   ->  Nested Loop (actual rows=1 loops=1)
+         ->  Append (actual rows=1 loops=1)
+               ->  Seq Scan on ab_a2_b1 (never executed)
+                     Filter: (b = $0)
+               ->  Seq Scan on ab_a2_b2 (actual rows=0 loops=1)
+                     Filter: (b = $0)
+               ->  Seq Scan on ab_a2_b3 (never executed)
+                     Filter: (b = $0)
+               ->  Subquery Scan on "*SELECT* 2_1" (actual rows=1 loops=1)
+                     ->  Result (actual rows=1 loops=1)
+                           One-Time Filter: (2 = $0)
+         ->  Index Scan using ab_a1_b2_a_idx on ab_a1_b2 (actual rows=1 loops=1)
+               Index Cond: (a = ab_a2_b1.a)
+   ->  Nested Loop (actual rows=1 loops=1)
+         ->  Append (actual rows=1 loops=1)
+               ->  Seq Scan on ab_a2_b1 (never executed)
+                     Filter: (b = $0)
+               ->  Seq Scan on ab_a2_b2 (actual rows=0 loops=1)
+                     Filter: (b = $0)
+               ->  Seq Scan on ab_a2_b3 (never executed)
+                     Filter: (b = $0)
+               ->  Subquery Scan on "*SELECT* 2_2" (actual rows=1 loops=1)
+                     ->  Result (actual rows=1 loops=1)
+                           One-Time Filter: (2 = $0)
+         ->  Index Scan using ab_a1_b3_a_idx on ab_a1_b3 (actual rows=1 loops=1)
+               Index Cond: (a = ab_a2_b1.a)
+(45 rows)
+
+table ab;
+ a | b 
+---+---
+ 1 | 3
+ 1 | 3
+ 1 | 3
+(3 rows)
+
+reset enable_hashjoin;
+reset enable_mergejoin;
 drop table ab, lprt_a;
 -- Join
 create table tbl1(col1 int);
diff --git a/src/test/regress/sql/partition_prune.sql b/src/test/regress/sql/partition_prune.sql
index 935c509b29..e78220a3e5 100644
--- a/src/test/regress/sql/partition_prune.sql
+++ b/src/test/regress/sql/partition_prune.sql
@@ -555,10 +555,19 @@ deallocate ab_q4;
 deallocate ab_q5;
 
 -- UPDATE on a partition subtree has been seen to have problems.
+set enable_hashjoin to off;
+set enable_mergejoin to off;
 insert into ab values (1,2);
 explain (analyze, costs off, summary off, timing off)
 update ab_a1 set b = 3 from ab where ab.a = 1 and ab.a = ab_a1.a;
 table ab;
+truncate ab;
+insert into ab values (1, 1), (1, 2), (1, 3);
+explain (analyze, costs off, summary off, timing off)
+update ab_a1 set b = 3 from (select * from (select * from ab_a2 union all select 1, 2) s where s.b = (select 2)) ss where ss.a = ab_a1.a;
+table ab;
+reset enable_hashjoin;
+reset enable_mergejoin;
 
 drop table ab, lprt_a;