Fix joins in RETURNING

To make it work, it is enough to properly pass the parent of the
PlanState while initializing the projection in RETURNING clause.

CHANGELOG.md

@@ -20,6 +20,7 @@ accidentally triggering the load of a previous DB version.**
 * #4575 Fix use of `get_partition_hash` and `get_partition_for_key` inside an IMMUTABLE function
 * #4611 Fix a potential OOM when loading large data sets into a hypertable
 * #4646 Fix time_bucket_ng origin handling
+* #4647 Fix the error "SubPlan found with no parent plan" that occurred if using joins in RETURNING clause.
 
 **Thanks**
 @AlmiS for reporting error on `get_partition_hash` executed inside an IMMUTABLE function
@@ -28,6 +29,7 @@ accidentally triggering the load of a previous DB version.**
 @michaelkitson for reporting permission errors using default privileges on Continuous Aggregates
 @ninjaltd and @mrksngl for reporting a potential OOM when loading large data sets into a hypertable
 @ssmoss for reporting an issue with time_bucket_ng origin handling
+@mwahlhuetter for reporting error in joins in RETURNING clause
 
 ## 2.7.2 (2022-07-26)
 

src/nodes/chunk_insert_state.c

@@ -160,7 +160,7 @@ get_adjusted_projection_info_returning(ProjectionInfo *orig, List *returning_cla
 	return ExecBuildProjectionInfo(returning_clauses,
 								   orig->pi_exprContext,
 								   orig->pi_state.resultslot,
-								   NULL,
+								   orig->pi_state.parent,
 								   chunk_desc);
 }
 

test/expected/insert_returning.out

@@ -0,0 +1,58 @@
+-- This file and its contents are licensed under the Apache License 2.0.
+-- Please see the included NOTICE for copyright information and
+-- LICENSE-APACHE for a copy of the license.
+CREATE TABLE standard_table (
+    standard_id integer PRIMARY KEY,
+    name text not null
+);
+CREATE TABLE hypertable (
+    time timestamptz not null,
+    name text not null,
+    standard_id integer not null
+);
+select * from create_hypertable('hypertable', 'time');
+ hypertable_id | schema_name | table_name | created 
+---------------+-------------+------------+---------
+             1 | public      | hypertable | t
+(1 row)
+
+INSERT INTO standard_table (standard_id, name)
+VALUES (1, 'standard_1');
+INSERT INTO hypertable (time, name, standard_id)
+VALUES ('2021-01-01 01:01:01+00', 'hypertable_1', 1);
+INSERT INTO hypertable (time, name, standard_id)
+VALUES ('2022-02-02 02:02:02+00', 'hypertable_2', 1)
+RETURNING *, EXISTS (
+  SELECT *
+  FROM standard_table
+  WHERE standard_table.standard_id = hypertable.standard_id
+);
+             time             |     name     | standard_id | exists 
+------------------------------+--------------+-------------+--------
+ Tue Feb 01 18:02:02 2022 PST | hypertable_2 |           1 | t
+(1 row)
+
+INSERT INTO hypertable (time, name, standard_id)
+VALUES ('2023-03-03 03:03:03+00', 'hypertable_3', 1)
+RETURNING *, EXISTS (
+  SELECT *
+  FROM standard_table
+  WHERE standard_table.standard_id = hypertable.standard_id
+);
+             time             |     name     | standard_id | exists 
+------------------------------+--------------+-------------+--------
+ Thu Mar 02 19:03:03 2023 PST | hypertable_3 |           1 | t
+(1 row)
+
+INSERT INTO hypertable (time, name, standard_id)
+VALUES ('2024-04-04 04:04:04+00', 'hypertable_4', 2)
+RETURNING *, EXISTS (
+  SELECT *
+  FROM standard_table
+  WHERE standard_table.standard_id = hypertable.standard_id
+);
+             time             |     name     | standard_id | exists 
+------------------------------+--------------+-------------+--------
+ Wed Apr 03 21:04:04 2024 PDT | hypertable_4 |           2 | f
+(1 row)
+

test/sql/CMakeLists.txt

@@ -26,6 +26,7 @@ set(TEST_FILES
     information_views.sql
     insert_many.sql
     insert_single.sql
+    insert_returning.sql
     lateral.sql
     misc.sql
     parallel.sql

test/sql/insert_returning.sql

@@ -0,0 +1,46 @@
+-- This file and its contents are licensed under the Apache License 2.0.
+-- Please see the included NOTICE for copyright information and
+-- LICENSE-APACHE for a copy of the license.
+
+CREATE TABLE standard_table (
+    standard_id integer PRIMARY KEY,
+    name text not null
+);
+
+CREATE TABLE hypertable (
+    time timestamptz not null,
+    name text not null,
+    standard_id integer not null
+);
+
+select * from create_hypertable('hypertable', 'time');
+
+INSERT INTO standard_table (standard_id, name)
+VALUES (1, 'standard_1');
+
+INSERT INTO hypertable (time, name, standard_id)
+VALUES ('2021-01-01 01:01:01+00', 'hypertable_1', 1);
+
+INSERT INTO hypertable (time, name, standard_id)
+VALUES ('2022-02-02 02:02:02+00', 'hypertable_2', 1)
+RETURNING *, EXISTS (
+  SELECT *
+  FROM standard_table
+  WHERE standard_table.standard_id = hypertable.standard_id
+);
+
+INSERT INTO hypertable (time, name, standard_id)
+VALUES ('2023-03-03 03:03:03+00', 'hypertable_3', 1)
+RETURNING *, EXISTS (
+  SELECT *
+  FROM standard_table
+  WHERE standard_table.standard_id = hypertable.standard_id
+);
+
+INSERT INTO hypertable (time, name, standard_id)
+VALUES ('2024-04-04 04:04:04+00', 'hypertable_4', 2)
+RETURNING *, EXISTS (
+  SELECT *
+  FROM standard_table
+  WHERE standard_table.standard_id = hypertable.standard_id
+);