diff -U3 /tmp/cirrus-ci-build/src/test/regress/expected/partition_aggregate.out /tmp/cirrus-ci-build/src/bin/pg_upgrade/tmp_check/results/partition_aggregate.out
--- /tmp/cirrus-ci-build/src/test/regress/expected/partition_aggregate.out	2025-12-08 16:03:13.975929863 +0000
+++ /tmp/cirrus-ci-build/src/bin/pg_upgrade/tmp_check/results/partition_aggregate.out	2025-12-08 16:11:51.882477986 +0000
@@ -521,23 +521,18 @@
    ->  IndexAggregate
          Group Key: t1.y
          Filter: (avg(t1.x) > '10'::numeric)
-         ->  Append
-               ->  Hash Join
-                     Hash Cond: (t1_1.x = t2_1.y)
+         ->  Hash Join
+               Hash Cond: (t1.x = t2.y)
+               ->  Append
                      ->  Seq Scan on pagg_tab1_p1 t1_1
-                     ->  Hash
-                           ->  Seq Scan on pagg_tab2_p1 t2_1
-               ->  Hash Join
-                     Hash Cond: (t1_2.x = t2_2.y)
                      ->  Seq Scan on pagg_tab1_p2 t1_2
-                     ->  Hash
+                     ->  Seq Scan on pagg_tab1_p3 t1_3
+               ->  Hash
+                     ->  Append
+                           ->  Seq Scan on pagg_tab2_p1 t2_1
                            ->  Seq Scan on pagg_tab2_p2 t2_2
-               ->  Hash Join
-                     Hash Cond: (t2_3.y = t1_3.x)
-                     ->  Seq Scan on pagg_tab2_p3 t2_3
-                     ->  Hash
-                           ->  Seq Scan on pagg_tab1_p3 t1_3
-(21 rows)
+                           ->  Seq Scan on pagg_tab2_p3 t2_3
+(16 rows)
 
 SELECT t1.y, sum(t1.x), count(*) FROM pagg_tab1 t1, pagg_tab2 t2 WHERE t1.x = t2.y GROUP BY t1.y HAVING avg(t1.x) > 10 ORDER BY 1, 2, 3;
  y  | sum  | count