Make sure the explain output for partition wise join is stable

We disable bunch of planning options on the workers. This might be
risky if any concurrent test relies on EXPLAIN OUTPUT as well. Still,
we want to keep this test, so we should try to not parallelize this
test with such test.

src/test/regress/expected/multi_partitioning.out

@@ -1562,29 +1562,70 @@ SELECT create_distributed_table('partitioning_hash_join_test', 'id');
  
 (1 row)
 
--- see the query plan without partition-wise join
+SELECT success FROM run_command_on_workers('alter system set enable_mergejoin to off');
-EXPLAIN
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system set enable_nestloop to off');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system set enable_indexscan to off');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system set enable_indexonlyscan to off');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system set enable_partitionwise_join to off');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('select pg_reload_conf()');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+EXPLAIN (COSTS OFF)
 SELECT * FROM partitioning_hash_test JOIN partitioning_hash_join_test USING (id, subid);
-                                                                                       QUERY PLAN                                                                                       
+                                                                                QUERY PLAN                                                                                
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------
- Custom Scan (Citus Real-Time)  (cost=0.00..0.00 rows=0 width=0)
+ Custom Scan (Citus Real-Time)
    Task Count: 4
    Tasks Shown: One of 4
    ->  Task
          Node: host=localhost port=57637 dbname=regression
-         ->  Merge Join  (cost=563.58..752.73 rows=383 width=8)
+         ->  Gather
-               Merge Cond: ((partitioning_hash_test.id = partitioning_hash_join_test.id) AND (partitioning_hash_test.subid = partitioning_hash_join_test.subid))
+               Workers Planned: 2
-               ->  Merge Append  (cost=0.43..123.59 rows=2262 width=8)
+               ->  Parallel Hash Join
-                     Sort Key: partitioning_hash_test.id, partitioning_hash_test.subid
+                     Hash Cond: ((partitioning_hash_join_test.id = partitioning_hash_test_1.id) AND (partitioning_hash_join_test.subid = partitioning_hash_test_1.subid))
-                     ->  Index Only Scan using partitioning_hash_test_0_1660016_pkey on partitioning_hash_test_0_1660016 partitioning_hash_test  (cost=0.12..8.14 rows=1 width=8)
+                     ->  Parallel Append
-                     ->  Index Only Scan using partitioning_hash_test_1_1660020_pkey on partitioning_hash_test_1_1660020 partitioning_hash_test_1  (cost=0.15..78.06 rows=2260 width=8)
+                           ->  Parallel Seq Scan on partitioning_hash_join_test_0_1660133 partitioning_hash_join_test
-                     ->  Index Only Scan using partitioning_hash_test_2_1660032_pkey on partitioning_hash_test_2_1660032 partitioning_hash_test_2  (cost=0.12..8.14 rows=1 width=8)
+                           ->  Parallel Seq Scan on partitioning_hash_join_test_1_1660137 partitioning_hash_join_test_1
-               ->  Sort  (cost=563.15..580.10 rows=6780 width=8)
+                           ->  Parallel Seq Scan on partitioning_hash_join_test_2_1660141 partitioning_hash_join_test_2
-                     Sort Key: partitioning_hash_join_test.id, partitioning_hash_join_test.subid
+                     ->  Parallel Hash
-                     ->  Append  (cost=0.00..131.70 rows=6780 width=8)
+                           ->  Parallel Append
-                           ->  Seq Scan on partitioning_hash_join_test_0_1660133 partitioning_hash_join_test  (cost=0.00..32.60 rows=2260 width=8)
+                                 ->  Parallel Seq Scan on partitioning_hash_test_1_1660020 partitioning_hash_test_1
-                           ->  Seq Scan on partitioning_hash_join_test_1_1660137 partitioning_hash_join_test_1  (cost=0.00..32.60 rows=2260 width=8)
+                                 ->  Parallel Seq Scan on partitioning_hash_test_0_1660016 partitioning_hash_test
-                           ->  Seq Scan on partitioning_hash_join_test_2_1660141 partitioning_hash_join_test_2  (cost=0.00..32.60 rows=2260 width=8)
+                                 ->  Parallel Seq Scan on partitioning_hash_test_2_1660032 partitioning_hash_test_2
 (18 rows)
 
 -- set partition-wise join on
@@ -1603,64 +1644,88 @@ SELECT success FROM run_command_on_workers('select pg_reload_conf()');
 (2 rows)
 
 SET enable_partitionwise_join TO on;
--- see the new query plan
+EXPLAIN (COSTS OFF)
-EXPLAIN
 SELECT * FROM partitioning_hash_test JOIN partitioning_hash_join_test USING (id, subid);
-                                                                                       QUERY PLAN                                                                                       
+                                                                                  QUERY PLAN                                                                                  
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
- Custom Scan (Citus Real-Time)  (cost=0.00..0.00 rows=0 width=0)
+ Custom Scan (Citus Real-Time)
    Task Count: 4
    Tasks Shown: One of 4
    ->  Task
          Node: host=localhost port=57637 dbname=regression
-         ->  Append  (cost=1.02..367.91 rows=130 width=8)
+         ->  Append
-               ->  Hash Join  (cost=1.02..50.59 rows=1 width=8)
+               ->  Hash Join
                      Hash Cond: ((partitioning_hash_join_test.id = partitioning_hash_test.id) AND (partitioning_hash_join_test.subid = partitioning_hash_test.subid))
-                     ->  Seq Scan on partitioning_hash_join_test_0_1660133 partitioning_hash_join_test  (cost=0.00..32.60 rows=2260 width=8)
+                     ->  Seq Scan on partitioning_hash_join_test_0_1660133 partitioning_hash_join_test
-                     ->  Hash  (cost=1.01..1.01 rows=1 width=8)
+                     ->  Hash
-                           ->  Seq Scan on partitioning_hash_test_0_1660016 partitioning_hash_test  (cost=0.00..1.01 rows=1 width=8)
+                           ->  Seq Scan on partitioning_hash_test_0_1660016 partitioning_hash_test
-               ->  Merge Join  (cost=158.66..266.09 rows=128 width=8)
+               ->  Hash Join
-                     Merge Cond: ((partitioning_hash_test_1.id = partitioning_hash_join_test_1.id) AND (partitioning_hash_test_1.subid = partitioning_hash_join_test_1.subid))
+                     Hash Cond: ((partitioning_hash_test_1.id = partitioning_hash_join_test_1.id) AND (partitioning_hash_test_1.subid = partitioning_hash_join_test_1.subid))
-                     ->  Index Only Scan using partitioning_hash_test_1_1660020_pkey on partitioning_hash_test_1_1660020 partitioning_hash_test_1  (cost=0.15..78.06 rows=2260 width=8)
+                     ->  Seq Scan on partitioning_hash_test_1_1660020 partitioning_hash_test_1
-                     ->  Sort  (cost=158.51..164.16 rows=2260 width=8)
+                     ->  Hash
-                           Sort Key: partitioning_hash_join_test_1.id, partitioning_hash_join_test_1.subid
+                           ->  Seq Scan on partitioning_hash_join_test_1_1660137 partitioning_hash_join_test_1
-                           ->  Seq Scan on partitioning_hash_join_test_1_1660137 partitioning_hash_join_test_1  (cost=0.00..32.60 rows=2260 width=8)
+               ->  Hash Join
-               ->  Hash Join  (cost=1.02..50.59 rows=1 width=8)
                      Hash Cond: ((partitioning_hash_join_test_2.id = partitioning_hash_test_2.id) AND (partitioning_hash_join_test_2.subid = partitioning_hash_test_2.subid))
-                     ->  Seq Scan on partitioning_hash_join_test_2_1660141 partitioning_hash_join_test_2  (cost=0.00..32.60 rows=2260 width=8)
+                     ->  Seq Scan on partitioning_hash_join_test_2_1660141 partitioning_hash_join_test_2
-                     ->  Hash  (cost=1.01..1.01 rows=1 width=8)
+                     ->  Hash
-                           ->  Seq Scan on partitioning_hash_test_2_1660032 partitioning_hash_test_2  (cost=0.00..1.01 rows=1 width=8)
+                           ->  Seq Scan on partitioning_hash_test_2_1660032 partitioning_hash_test_2
-(22 rows)
+(21 rows)
 
 -- note that partition-wise joins only work when partition key is in the join
 -- following join does not have that, therefore join will not be pushed down to
 -- partitions
-EXPLAIN
+EXPLAIN (COSTS OFF)
 SELECT * FROM partitioning_hash_test JOIN partitioning_hash_join_test USING (id);
-                                                                                       QUERY PLAN                                                                                       
+                                               QUERY PLAN                                                
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+---------------------------------------------------------------------------------------------------------
- Custom Scan (Citus Real-Time)  (cost=0.00..0.00 rows=0 width=0)
+ Custom Scan (Citus Real-Time)
    Task Count: 4
    Tasks Shown: One of 4
    ->  Task
          Node: host=localhost port=57637 dbname=regression
-         ->  Merge Join  (cost=563.58..1842.63 rows=76682 width=12)
+         ->  Hash Join
-               Merge Cond: (partitioning_hash_test.id = partitioning_hash_join_test.id)
+               Hash Cond: (partitioning_hash_join_test.id = partitioning_hash_test.id)
-               ->  Merge Append  (cost=0.43..123.59 rows=2262 width=8)
+               ->  Append
-                     Sort Key: partitioning_hash_test.id
+                     ->  Seq Scan on partitioning_hash_join_test_0_1660133 partitioning_hash_join_test
-                     ->  Index Only Scan using partitioning_hash_test_0_1660016_pkey on partitioning_hash_test_0_1660016 partitioning_hash_test  (cost=0.12..8.14 rows=1 width=8)
+                     ->  Seq Scan on partitioning_hash_join_test_1_1660137 partitioning_hash_join_test_1
-                     ->  Index Only Scan using partitioning_hash_test_1_1660020_pkey on partitioning_hash_test_1_1660020 partitioning_hash_test_1  (cost=0.15..78.06 rows=2260 width=8)
+                     ->  Seq Scan on partitioning_hash_join_test_2_1660141 partitioning_hash_join_test_2
-                     ->  Index Only Scan using partitioning_hash_test_2_1660032_pkey on partitioning_hash_test_2_1660032 partitioning_hash_test_2  (cost=0.12..8.14 rows=1 width=8)
+               ->  Hash
-               ->  Sort  (cost=563.15..580.10 rows=6780 width=8)
+                     ->  Append
-                     Sort Key: partitioning_hash_join_test.id
+                           ->  Seq Scan on partitioning_hash_test_0_1660016 partitioning_hash_test
-                     ->  Append  (cost=0.00..131.70 rows=6780 width=8)
+                           ->  Seq Scan on partitioning_hash_test_1_1660020 partitioning_hash_test_1
-                           ->  Seq Scan on partitioning_hash_join_test_0_1660133 partitioning_hash_join_test  (cost=0.00..32.60 rows=2260 width=8)
+                           ->  Seq Scan on partitioning_hash_test_2_1660032 partitioning_hash_test_2
-                           ->  Seq Scan on partitioning_hash_join_test_1_1660137 partitioning_hash_join_test_1  (cost=0.00..32.60 rows=2260 width=8)
+(16 rows)
-                           ->  Seq Scan on partitioning_hash_join_test_2_1660141 partitioning_hash_join_test_2  (cost=0.00..32.60 rows=2260 width=8)
-(18 rows)
 
 -- reset partition-wise join
-SELECT success FROM run_command_on_workers('reset enable_partitionwise_join');
+SELECT success FROM run_command_on_workers('alter system reset enable_partitionwise_join');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system reset enable_mergejoin');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system reset enable_nestloop');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system reset enable_indexscan');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system reset enable_indexonlyscan');
  success 
 ---------
  t

src/test/regress/expected/multi_partitioning_0.out

@@ -1542,8 +1542,49 @@ SELECT create_distributed_table('partitioning_hash_join_test', 'id');
 ERROR:  relation "partitioning_hash_join_test" does not exist
 LINE 1: SELECT create_distributed_table('partitioning_hash_join_test...
                                         ^
--- see the query plan without partition-wise join
+SELECT success FROM run_command_on_workers('alter system set enable_mergejoin to off');
-EXPLAIN
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system set enable_nestloop to off');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system set enable_indexscan to off');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system set enable_indexonlyscan to off');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system set enable_partitionwise_join to off');
+ success 
+---------
+ f
+ f
+(2 rows)
+
+SELECT success FROM run_command_on_workers('select pg_reload_conf()');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+EXPLAIN (COSTS OFF)
 SELECT * FROM partitioning_hash_test JOIN partitioning_hash_join_test USING (id, subid);
 ERROR:  relation "partitioning_hash_test" does not exist
 LINE 2: SELECT * FROM partitioning_hash_test JOIN partitioning_hash_...
@@ -1565,8 +1606,7 @@ SELECT success FROM run_command_on_workers('select pg_reload_conf()');
 
 SET enable_partitionwise_join TO on;
 ERROR:  unrecognized configuration parameter "enable_partitionwise_join"
--- see the new query plan
+EXPLAIN (COSTS OFF)
-EXPLAIN
 SELECT * FROM partitioning_hash_test JOIN partitioning_hash_join_test USING (id, subid);
 ERROR:  relation "partitioning_hash_test" does not exist
 LINE 2: SELECT * FROM partitioning_hash_test JOIN partitioning_hash_...
@@ -1574,19 +1614,47 @@ LINE 2: SELECT * FROM partitioning_hash_test JOIN partitioning_hash_...
 -- note that partition-wise joins only work when partition key is in the join
 -- following join does not have that, therefore join will not be pushed down to
 -- partitions
-EXPLAIN
+EXPLAIN (COSTS OFF)
 SELECT * FROM partitioning_hash_test JOIN partitioning_hash_join_test USING (id);
 ERROR:  relation "partitioning_hash_test" does not exist
 LINE 2: SELECT * FROM partitioning_hash_test JOIN partitioning_hash_...
                       ^
 -- reset partition-wise join
-SELECT success FROM run_command_on_workers('reset enable_partitionwise_join');
+SELECT success FROM run_command_on_workers('alter system reset enable_partitionwise_join');
  success 
 ---------
  f
  f
 (2 rows)
 
+SELECT success FROM run_command_on_workers('alter system reset enable_mergejoin');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system reset enable_nestloop');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system reset enable_indexscan');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system reset enable_indexonlyscan');
+ success 
+---------
+ t
+ t
+(2 rows)
+
 SELECT success FROM run_command_on_workers('select pg_reload_conf()');
  success 
 ---------

src/test/regress/expected/multi_partitioning_1.out

@@ -1420,8 +1420,49 @@ SELECT create_distributed_table('partitioning_hash_join_test', 'id');
 ERROR:  relation "partitioning_hash_join_test" does not exist
 LINE 1: SELECT create_distributed_table('partitioning_hash_join_test...
                                         ^
--- see the query plan without partition-wise join
+SELECT success FROM run_command_on_workers('alter system set enable_mergejoin to off');
-EXPLAIN
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system set enable_nestloop to off');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system set enable_indexscan to off');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system set enable_indexonlyscan to off');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system set enable_partitionwise_join to off');
+ success 
+---------
+ f
+ f
+(2 rows)
+
+SELECT success FROM run_command_on_workers('select pg_reload_conf()');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+EXPLAIN (COSTS OFF)
 SELECT * FROM partitioning_hash_test JOIN partitioning_hash_join_test USING (id, subid);
 ERROR:  relation "partitioning_hash_test" does not exist
 LINE 2: SELECT * FROM partitioning_hash_test JOIN partitioning_hash_...
@@ -1443,8 +1484,7 @@ SELECT success FROM run_command_on_workers('select pg_reload_conf()');
 
 SET enable_partitionwise_join TO on;
 ERROR:  unrecognized configuration parameter "enable_partitionwise_join"
--- see the new query plan
+EXPLAIN (COSTS OFF)
-EXPLAIN
 SELECT * FROM partitioning_hash_test JOIN partitioning_hash_join_test USING (id, subid);
 ERROR:  relation "partitioning_hash_test" does not exist
 LINE 2: SELECT * FROM partitioning_hash_test JOIN partitioning_hash_...
@@ -1452,19 +1492,47 @@ LINE 2: SELECT * FROM partitioning_hash_test JOIN partitioning_hash_...
 -- note that partition-wise joins only work when partition key is in the join
 -- following join does not have that, therefore join will not be pushed down to
 -- partitions
-EXPLAIN
+EXPLAIN (COSTS OFF)
 SELECT * FROM partitioning_hash_test JOIN partitioning_hash_join_test USING (id);
 ERROR:  relation "partitioning_hash_test" does not exist
 LINE 2: SELECT * FROM partitioning_hash_test JOIN partitioning_hash_...
                       ^
 -- reset partition-wise join
-SELECT success FROM run_command_on_workers('reset enable_partitionwise_join');
+SELECT success FROM run_command_on_workers('alter system reset enable_partitionwise_join');
  success 
 ---------
  f
  f
 (2 rows)
 
+SELECT success FROM run_command_on_workers('alter system reset enable_mergejoin');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system reset enable_nestloop');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system reset enable_indexscan');
+ success 
+---------
+ t
+ t
+(2 rows)
+
+SELECT success FROM run_command_on_workers('alter system reset enable_indexonlyscan');
+ success 
+---------
+ t
+ t
+(2 rows)
+
 SELECT success FROM run_command_on_workers('select pg_reload_conf()');
  success 
 ---------

src/test/regress/sql/multi_partitioning.sql

@@ -986,7 +986,6 @@ ORDER BY
 COMMIT;
 
 -- test partition-wise join
-
 CREATE TABLE partitioning_hash_join_test(id int, subid int) PARTITION BY HASH(subid);
 CREATE TABLE partitioning_hash_join_test_0 PARTITION OF partitioning_hash_join_test FOR VALUES WITH (MODULUS 3, REMAINDER 0);
 CREATE TABLE partitioning_hash_join_test_1 PARTITION OF partitioning_hash_join_test FOR VALUES WITH (MODULUS 3, REMAINDER 1);
@@ -994,8 +993,14 @@ CREATE TABLE partitioning_hash_join_test_2 PARTITION OF partitioning_hash_join_t
 
 SELECT create_distributed_table('partitioning_hash_join_test', 'id');
 
--- see the query plan without partition-wise join
+SELECT success FROM run_command_on_workers('alter system set enable_mergejoin to off');
-EXPLAIN
+SELECT success FROM run_command_on_workers('alter system set enable_nestloop to off');
+SELECT success FROM run_command_on_workers('alter system set enable_indexscan to off');
+SELECT success FROM run_command_on_workers('alter system set enable_indexonlyscan to off');
+SELECT success FROM run_command_on_workers('alter system set enable_partitionwise_join to off');
+SELECT success FROM run_command_on_workers('select pg_reload_conf()');
+
+EXPLAIN (COSTS OFF)
 SELECT * FROM partitioning_hash_test JOIN partitioning_hash_join_test USING (id, subid);
 
 -- set partition-wise join on
@@ -1004,18 +1009,21 @@ SELECT success FROM run_command_on_workers('select pg_reload_conf()');
 
 SET enable_partitionwise_join TO on;
 
--- see the new query plan
+EXPLAIN (COSTS OFF)
-EXPLAIN
 SELECT * FROM partitioning_hash_test JOIN partitioning_hash_join_test USING (id, subid);
 
 -- note that partition-wise joins only work when partition key is in the join
 -- following join does not have that, therefore join will not be pushed down to
 -- partitions
-EXPLAIN
+EXPLAIN (COSTS OFF)
 SELECT * FROM partitioning_hash_test JOIN partitioning_hash_join_test USING (id);
 
 -- reset partition-wise join
-SELECT success FROM run_command_on_workers('reset enable_partitionwise_join');
+SELECT success FROM run_command_on_workers('alter system reset enable_partitionwise_join');
+SELECT success FROM run_command_on_workers('alter system reset enable_mergejoin');
+SELECT success FROM run_command_on_workers('alter system reset enable_nestloop');
+SELECT success FROM run_command_on_workers('alter system reset enable_indexscan');
+SELECT success FROM run_command_on_workers('alter system reset enable_indexonlyscan');
 SELECT success FROM run_command_on_workers('select pg_reload_conf()');
 
 RESET enable_partitionwise_join;