Fix tablespace handling in MERGE/SPLIT partition commands.

As commit ca4103025d stated, new partitions without a specified tablespace
should inherit the parent relation's tablespace. However, previously,
ALTER TABLE MERGE PARTITIONS and ALTER TABLE SPLIT PARTITION commands
always created new partitions in the default tablespace, ignoring
the parent's tablespace. This commit ensures new partitions inherit
the parent's tablespace.

Backpatch to v17 where these commands were introduced.

Author: Fujii Masao
Reviewed-by: Masahiko Sawada
Discussion: https://postgr.es/m/abaf390b-3320-40a5-8815-ef476db5cfe7@oss.nttdata.com

5 files changed, 75 insertions, 1 deletions

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index b0bc9140138..721d24783b4 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -20340,7 +20340,7 @@ createPartitionTable(RangeVar *newPartName, Relation modelRel,
 	createStmt->constraints = NIL;
 	createStmt->options = NIL;
 	createStmt->oncommit = ONCOMMIT_NOOP;
-	createStmt->tablespacename = NULL;
+	createStmt->tablespacename = get_tablespace_name(modelRel->rd_rel->reltablespace);
 	createStmt->if_not_exists = false;
 	createStmt->accessMethod = get_am_name(modelRel->rd_rel->relam);
 
diff --git a/src/test/regress/expected/partition_merge.out b/src/test/regress/expected/partition_merge.out
index 9c67a4a8b15..26bf58b23db 100644
--- a/src/test/regress/expected/partition_merge.out
+++ b/src/test/regress/expected/partition_merge.out
@@ -861,6 +861,29 @@ SET search_path = partitions_merge_schema, pg_temp, public;
 -- Can't merge temporary partitions into a persistent partition
 ALTER TABLE t MERGE PARTITIONS (tp_0_1, tp_1_2) INTO tp_0_2;
 ROLLBACK;
+-- Check the new partition inherits parent's tablespace
+CREATE TABLE t (i int PRIMARY KEY USING INDEX TABLESPACE regress_tblspace)
+  PARTITION BY RANGE (i) TABLESPACE regress_tblspace;
+CREATE TABLE tp_0_1 PARTITION OF t FOR VALUES FROM (0) TO (1);
+CREATE TABLE tp_1_2 PARTITION OF t FOR VALUES FROM (1) TO (2);
+ALTER TABLE t MERGE PARTITIONS (tp_0_1, tp_1_2) INTO tp_0_2;
+SELECT tablename, tablespace FROM pg_tables
+  WHERE tablename IN ('t', 'tp_0_2') ORDER BY tablename, tablespace;
+ tablename |    tablespace    
+-----------+------------------
+ t         | regress_tblspace
+ tp_0_2    | regress_tblspace
+(2 rows)
+
+SELECT tablename, indexname, tablespace FROM pg_indexes
+  WHERE tablename IN ('t', 'tp_0_2') ORDER BY tablename, indexname, tablespace;
+ tablename |  indexname  |    tablespace    
+-----------+-------------+------------------
+ t         | t_pkey      | regress_tblspace
+ tp_0_2    | tp_0_2_pkey | regress_tblspace
+(2 rows)
+
+DROP TABLE t;
 -- Check the new partition inherits parent's table access method
 SET search_path = partitions_merge_schema, public;
 CREATE ACCESS METHOD partitions_merge_heap TYPE TABLE HANDLER heap_tableam_handler;
diff --git a/src/test/regress/expected/partition_split.out b/src/test/regress/expected/partition_split.out
index 5fbfc8f8056..1a8c95ad819 100644
--- a/src/test/regress/expected/partition_split.out
+++ b/src/test/regress/expected/partition_split.out
@@ -1494,6 +1494,32 @@ SELECT c.oid::pg_catalog.regclass, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
 (2 rows)
 
 DROP TABLE t;
+-- Check the new partitions inherit parent's tablespace
+CREATE TABLE t (i int PRIMARY KEY USING INDEX TABLESPACE regress_tblspace)
+  PARTITION BY RANGE (i) TABLESPACE regress_tblspace;
+CREATE TABLE tp_0_2 PARTITION OF t FOR VALUES FROM (0) TO (2);
+ALTER TABLE t SPLIT PARTITION tp_0_2 INTO
+  (PARTITION tp_0_1 FOR VALUES FROM (0) TO (1),
+   PARTITION tp_1_2 FOR VALUES FROM (1) TO (2));
+SELECT tablename, tablespace FROM pg_tables
+  WHERE tablename IN ('t', 'tp_0_1', 'tp_1_2') ORDER BY tablename, tablespace;
+ tablename |    tablespace    
+-----------+------------------
+ t         | regress_tblspace
+ tp_0_1    | regress_tblspace
+ tp_1_2    | regress_tblspace
+(3 rows)
+
+SELECT tablename, indexname, tablespace FROM pg_indexes
+  WHERE tablename IN ('t', 'tp_0_1', 'tp_1_2') ORDER BY tablename, indexname, tablespace;
+ tablename |  indexname  |    tablespace    
+-----------+-------------+------------------
+ t         | t_pkey      | regress_tblspace
+ tp_0_1    | tp_0_1_pkey | regress_tblspace
+ tp_1_2    | tp_1_2_pkey | regress_tblspace
+(3 rows)
+
+DROP TABLE t;
 -- Check new partitions inherits parent's table access method
 CREATE ACCESS METHOD partition_split_heap TYPE TABLE HANDLER heap_tableam_handler;
 CREATE TABLE t (i int) PARTITION BY RANGE (i) USING partition_split_heap;
diff --git a/src/test/regress/sql/partition_merge.sql b/src/test/regress/sql/partition_merge.sql
index 56249732002..200bd3e7620 100644
--- a/src/test/regress/sql/partition_merge.sql
+++ b/src/test/regress/sql/partition_merge.sql
@@ -536,6 +536,18 @@ SET search_path = partitions_merge_schema, pg_temp, public;
 ALTER TABLE t MERGE PARTITIONS (tp_0_1, tp_1_2) INTO tp_0_2;
 ROLLBACK;
 
+-- Check the new partition inherits parent's tablespace
+CREATE TABLE t (i int PRIMARY KEY USING INDEX TABLESPACE regress_tblspace)
+  PARTITION BY RANGE (i) TABLESPACE regress_tblspace;
+CREATE TABLE tp_0_1 PARTITION OF t FOR VALUES FROM (0) TO (1);
+CREATE TABLE tp_1_2 PARTITION OF t FOR VALUES FROM (1) TO (2);
+ALTER TABLE t MERGE PARTITIONS (tp_0_1, tp_1_2) INTO tp_0_2;
+SELECT tablename, tablespace FROM pg_tables
+  WHERE tablename IN ('t', 'tp_0_2') ORDER BY tablename, tablespace;
+SELECT tablename, indexname, tablespace FROM pg_indexes
+  WHERE tablename IN ('t', 'tp_0_2') ORDER BY tablename, indexname, tablespace;
+DROP TABLE t;
+
 -- Check the new partition inherits parent's table access method
 SET search_path = partitions_merge_schema, public;
 CREATE ACCESS METHOD partitions_merge_heap TYPE TABLE HANDLER heap_tableam_handler;
diff --git a/src/test/regress/sql/partition_split.sql b/src/test/regress/sql/partition_split.sql
index 9c7d47963c1..5143d85ec01 100644
--- a/src/test/regress/sql/partition_split.sql
+++ b/src/test/regress/sql/partition_split.sql
@@ -880,6 +880,19 @@ SELECT c.oid::pg_catalog.regclass, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
 
 DROP TABLE t;
 
+-- Check the new partitions inherit parent's tablespace
+CREATE TABLE t (i int PRIMARY KEY USING INDEX TABLESPACE regress_tblspace)
+  PARTITION BY RANGE (i) TABLESPACE regress_tblspace;
+CREATE TABLE tp_0_2 PARTITION OF t FOR VALUES FROM (0) TO (2);
+ALTER TABLE t SPLIT PARTITION tp_0_2 INTO
+  (PARTITION tp_0_1 FOR VALUES FROM (0) TO (1),
+   PARTITION tp_1_2 FOR VALUES FROM (1) TO (2));
+SELECT tablename, tablespace FROM pg_tables
+  WHERE tablename IN ('t', 'tp_0_1', 'tp_1_2') ORDER BY tablename, tablespace;
+SELECT tablename, indexname, tablespace FROM pg_indexes
+  WHERE tablename IN ('t', 'tp_0_1', 'tp_1_2') ORDER BY tablename, indexname, tablespace;
+DROP TABLE t;
+
 -- Check new partitions inherits parent's table access method
 CREATE ACCESS METHOD partition_split_heap TYPE TABLE HANDLER heap_tableam_handler;
 CREATE TABLE t (i int) PARTITION BY RANGE (i) USING partition_split_heap;