BUG #19390: Defects in the test case partition_merge - Mailing list pgsql-bugs

The following bug has been logged on the website:

Bug reference:      19390
Logged by:          fairyfar
Email address:      fairyfar@msn.com
PostgreSQL version: Unsupported/Unknown
Operating system:   Linux
Description:

# PostgreSQL version

git branch: master
git commit id: 851f6649cc18c4b482fa2b6afddb65b35d035370

# Problem

In my test environment, the next OID of PostgreSQL is greater than 2^31.
The partition_merge failure in regression testing:

```bash
[yz@bogon regress]$ ./pg_regress --schedule=parallel_schedule
...
# parallel group (18 tests):  compression_lz4 numa hash_part explain
reloptions predicate partition_info compression memoize eager_aggregate
tuplesort partition_aggregate partition_merge partition_split
partition_prune indexing partition_join stats
not ok 215   + partition_merge                         16421 ms
...

[yz@bogon regress]$ cat regression.diffs
diff -U3
/home/yz/postgresql/postgres_src/src/test/regress/expected/partition_merge.out
/home/yz/postgresql/postgres_src/src/test/regress/results/partition_merge.out
---
/home/yz/postgresql/postgres_src/src/test/regress/expected/partition_merge.out
2026-01-27 14:36:29.093904247 +0800
+++
/home/yz/postgresql/postgres_src/src/test/regress/results/partition_merge.out
2026-01-28 14:51:09.227253112 +0800
@@ -1068,26 +1068,27 @@
 ALTER TABLE t ADD CHECK (g > 0);
 ALTER TABLE t ADD CHECK (i > 0);
 INSERT INTO t VALUES (5), (15);
+ERROR:  new row for relation "tp_1" violates check constraint "t_g_check"
+DETAIL:  Failing row contains (5, virtual).
 ALTER TABLE t MERGE PARTITIONS (tp_1, tp_2) INTO tp_12;
 INSERT INTO t VALUES (16);
+ERROR:  new row for relation "tp_12" violates check constraint "t_g_check"
+DETAIL:  Failing row contains (16, virtual).
 -- ERROR:  new row for relation "tp_12" violates check constraint
"t_i_check"
 INSERT INTO t VALUES (0);
-ERROR:  new row for relation "tp_12" violates check constraint "t_i_check"
+ERROR:  new row for relation "tp_12" violates check constraint "t_g_check"
 DETAIL:  Failing row contains (0, virtual).
 -- Should be 3 rows: (5), (15), (16):
 SELECT i FROM t ORDER BY i;
- i
-----
-  5
- 15
- 16
-(3 rows)
+ i
+---
+(0 rows)

 -- Should be 1 because for the same tableoid (15 + tableoid) = (5 +
tableoid) + 10:
 SELECT count(*) FROM t WHERE i = 15 AND g IN (SELECT g + 10 FROM t WHERE i
= 5);
  count
 -------
-     1
+     0
 (1 row)

 DROP TABLE t;
```

# Root Cause

OID is unsigned int. So, when OID is greater than 2^n, converting it to int
will result in a negative value.

# Solution

```bash
[yz@bogon postgres_src]$ git diff
diff --git a/src/test/regress/expected/partition_merge.out
b/src/test/regress/expected/partition_merge.out
index 925fe4f570a..75d1e42511e 100644
--- a/src/test/regress/expected/partition_merge.out
+++ b/src/test/regress/expected/partition_merge.out
@@ -1033,7 +1033,7 @@ DETAIL:  Key (i)=(2) is not present in table "t".
 DROP TABLE t_fk;
 DROP TABLE t;
 -- Test for recomputation of stored generated columns.
-CREATE TABLE t (i int, tab_id int generated always as (tableoid) stored)
PARTITION BY RANGE (i);
+CREATE TABLE t (i bigint, tab_id bigint generated always as (tableoid)
stored) PARTITION BY RANGE (i);
 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 ADD CONSTRAINT cc CHECK(tableoid <> 123456789);
@@ -1060,9 +1060,9 @@ SELECT count(*) FROM t WHERE i = 0 AND tab_id IN
(SELECT tab_id FROM t WHERE i =
 DROP TABLE t;
 -- Test for generated columns (different order of columns in partitioned
table
 -- and partitions).
-CREATE TABLE t (i int, g int GENERATED ALWAYS AS (i + tableoid::int))
PARTITION BY RANGE (i);
-CREATE TABLE tp_1 (g int GENERATED ALWAYS AS (i + tableoid::int), i int);
-CREATE TABLE tp_2 (g int GENERATED ALWAYS AS (i + tableoid::int), i int);
+CREATE TABLE t (i bigint, g bigint GENERATED ALWAYS AS (i +
tableoid::bigint)) PARTITION BY RANGE (i);
+CREATE TABLE tp_1 (g bigint GENERATED ALWAYS AS (i + tableoid::bigint), i
bigint);
+CREATE TABLE tp_2 (g bigint GENERATED ALWAYS AS (i + tableoid::bigint), i
bigint);
 ALTER TABLE t ATTACH PARTITION tp_1 FOR VALUES FROM (-1) TO (10);
 ALTER TABLE t ATTACH PARTITION tp_2 FOR VALUES FROM (10) TO (20);
 ALTER TABLE t ADD CHECK (g > 0);
diff --git a/src/test/regress/sql/partition_merge.sql
b/src/test/regress/sql/partition_merge.sql
index a211fee2ad1..721a313fbd4 100644
--- a/src/test/regress/sql/partition_merge.sql
+++ b/src/test/regress/sql/partition_merge.sql
@@ -739,7 +739,7 @@ DROP TABLE t;


 -- Test for recomputation of stored generated columns.
-CREATE TABLE t (i int, tab_id int generated always as (tableoid) stored)
PARTITION BY RANGE (i);
+CREATE TABLE t (i bigint, tab_id bigint generated always as (tableoid)
stored) PARTITION BY RANGE (i);
 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 ADD CONSTRAINT cc CHECK(tableoid <> 123456789);
@@ -762,9 +762,9 @@ DROP TABLE t;

 -- Test for generated columns (different order of columns in partitioned
table
 -- and partitions).
-CREATE TABLE t (i int, g int GENERATED ALWAYS AS (i + tableoid::int))
PARTITION BY RANGE (i);
-CREATE TABLE tp_1 (g int GENERATED ALWAYS AS (i + tableoid::int), i int);
-CREATE TABLE tp_2 (g int GENERATED ALWAYS AS (i + tableoid::int), i int);
+CREATE TABLE t (i bigint, g bigint GENERATED ALWAYS AS (i +
tableoid::bigint)) PARTITION BY RANGE (i);
+CREATE TABLE tp_1 (g bigint GENERATED ALWAYS AS (i + tableoid::bigint), i
bigint);
+CREATE TABLE tp_2 (g bigint GENERATED ALWAYS AS (i + tableoid::bigint), i
bigint);
 ALTER TABLE t ATTACH PARTITION tp_1 FOR VALUES FROM (-1) TO (10);
 ALTER TABLE t ATTACH PARTITION tp_2 FOR VALUES FROM (10) TO (20);
 ALTER TABLE t ADD CHECK (g > 0);
```