diff --git a/src/test/regress/expected/aggregates.out b/src/test/regress/expected/aggregates.out
index f85e913..fa56f6b 100644
--- a/src/test/regress/expected/aggregates.out
+++ b/src/test/regress/expected/aggregates.out
@@ -2065,3 +2065,48 @@ SELECT balk(hundred) FROM tenk1;
 (1 row)

 ROLLBACK;
+-- Test for partially_grouped_rel
+SET parallel_setup_cost=0;
+SET parallel_tuple_cost=0;
+SET enable_hashagg TO false;
+CREATE TABLE pagg_tab1(x int, y int) PARTITION BY RANGE(x);
+CREATE TABLE pagg_tab1_p1 PARTITION OF pagg_tab1 FOR VALUES FROM (0) TO (10);
+CREATE TABLE pagg_tab1_p2 PARTITION OF pagg_tab1 FOR VALUES FROM (10) TO (20);
+CREATE TABLE pagg_tab1_p3 PARTITION OF pagg_tab1 FOR VALUES FROM (20) TO (30);
+CREATE TABLE pagg_tab2(x int, y int) PARTITION BY RANGE(y);
+CREATE TABLE pagg_tab2_p1 PARTITION OF pagg_tab2 FOR VALUES FROM (0) TO (10);
+CREATE TABLE pagg_tab2_p2 PARTITION OF pagg_tab2 FOR VALUES FROM (10) TO (20);
+CREATE TABLE pagg_tab2_p3 PARTITION OF pagg_tab2 FOR VALUES FROM (20) TO (30);
+INSERT INTO pagg_tab1 SELECT i%30, i FROM generate_series(0, 29) i;
+INSERT INTO pagg_tab2 SELECT i, i%30 FROM generate_series(0, 29) i;
+ANALYZE pagg_tab1;
+ANALYZE pagg_tab2;
+EXPLAIN (COSTS OFF)
+SELECT t1.y, sum(t1.x), COUNT(*) FROM pagg_tab1 t1, pagg_tab2 t2 WHERE t1.x = t2.y GROUP BY t1.y ORDER BY 1, 2, 3;
+                                       QUERY PLAN                                       
+----------------------------------------------------------------------------------------
+ Sort
+   Sort Key: t1.y, (sum(t1.x)), (count(*))
+   ->  Finalize GroupAggregate
+         Group Key: t1.y
+         ->  Gather Merge
+               Workers Planned: 2
+               ->  Partial GroupAggregate
+                     Group Key: t1.y
+                     ->  Sort
+                           Sort Key: t1.y
+                           ->  Parallel Hash Join
+                                 Hash Cond: (t1.x = t2.y)
+                                 ->  Parallel Append
+                                       ->  Parallel Seq Scan on pagg_tab1_p1 t1
+                                       ->  Parallel Seq Scan on pagg_tab1_p2 t1_1
+                                       ->  Parallel Seq Scan on pagg_tab1_p3 t1_2
+                                 ->  Parallel Hash
+                                       ->  Parallel Append
+                                             ->  Parallel Seq Scan on pagg_tab2_p1 t2
+                                             ->  Parallel Seq Scan on pagg_tab2_p2 t2_1
+                                             ->  Parallel Seq Scan on pagg_tab2_p3 t2_2
+(21 rows)
+
+DROP TABLE pagg_tab2;
+DROP TABLE pagg_tab1;
diff --git a/src/test/regress/sql/aggregates.sql b/src/test/regress/sql/aggregates.sql
index 506d044..17c25e5 100644
--- a/src/test/regress/sql/aggregates.sql
+++ b/src/test/regress/sql/aggregates.sql
@@ -907,3 +907,30 @@ EXPLAIN (COSTS OFF) SELECT balk(hundred) FROM tenk1;
 SELECT balk(hundred) FROM tenk1;

 ROLLBACK;
+
+-- Test for partially_grouped_rel
+SET parallel_setup_cost=0;
+SET parallel_tuple_cost=0;
+SET enable_hashagg TO false;
+
+CREATE TABLE pagg_tab1(x int, y int) PARTITION BY RANGE(x);
+CREATE TABLE pagg_tab1_p1 PARTITION OF pagg_tab1 FOR VALUES FROM (0) TO (10);
+CREATE TABLE pagg_tab1_p2 PARTITION OF pagg_tab1 FOR VALUES FROM (10) TO (20);
+CREATE TABLE pagg_tab1_p3 PARTITION OF pagg_tab1 FOR VALUES FROM (20) TO (30);
+
+CREATE TABLE pagg_tab2(x int, y int) PARTITION BY RANGE(y);
+CREATE TABLE pagg_tab2_p1 PARTITION OF pagg_tab2 FOR VALUES FROM (0) TO (10);
+CREATE TABLE pagg_tab2_p2 PARTITION OF pagg_tab2 FOR VALUES FROM (10) TO (20);
+CREATE TABLE pagg_tab2_p3 PARTITION OF pagg_tab2 FOR VALUES FROM (20) TO (30);
+
+INSERT INTO pagg_tab1 SELECT i%30, i FROM generate_series(0, 29) i;
+INSERT INTO pagg_tab2 SELECT i, i%30 FROM generate_series(0, 29) i;
+
+ANALYZE pagg_tab1;
+ANALYZE pagg_tab2;
+
+EXPLAIN (COSTS OFF)
+SELECT t1.y, sum(t1.x), COUNT(*) FROM pagg_tab1 t1, pagg_tab2 t2 WHERE t1.x = t2.y GROUP BY t1.y ORDER BY 1, 2, 3;
+
+DROP TABLE pagg_tab2;
+DROP TABLE pagg_tab1;