Re: Self referential foreign keys in partitioned table not working as expected
Luca Vallisa <luca.vallisa@gmail.com>
From: Luca Vallisa <luca.vallisa@gmail.com>
To: Christoph Berg <myon@debian.org>
Cc: pgsql-bugs@lists.postgresql.org
Date: 2025-04-01T10:24:46Z
Lists: pgsql-bugs, pgsql-hackers
Thanks for the reply.
I've realized I messed up with the script.
Please refer to the following one.
---------------------------------------------------------------------------------------
drop table if exists test;
create table test (
id_1 int4 not null,
id_2 int4 not null,
parent_id_2 int4 null,
primary key (id_1, id_2),
foreign key (id_1, parent_id_2) references test (id_1, id_2)
)
--partition by list (id_1); /** uncomment this line **/
--create table test_1 partition of test for values in (1); /** uncomment
this line **/
--create table test_9 partition of test for values in (9) /** uncomment
this line **/
;
insert into test values (1, 1, null), (1, 2, 1);
delete from test where (id_1, id_2) = (1, 1);
--update test set id_2 = 9 where (id_1, id_2) = (1, 1);
select * from test;
drop table if exists test;
---------------------------------------------------------------------------------------
The provided version throws an error.
If you uncomment the 3 lines (working with partition) the error is not
thrown during the delete (or the update).
Luca
Il giorno mar 1 apr 2025 alle ore 12:18 Christoph Berg <myon@debian.org> ha
scritto:
> Re: Luca Vallisa
> > create table test (
> > id_1 int4 not null,
> > id_2 int4 not null,
> > parent_id_1 int4 null,
> > primary key (id_1, id_2),
> > foreign key (parent_id_1, id_2) references test(id_1, id_2)
> > ) partition by list(id_1);
> >
> > insert into test values (1, 1, null), (1, 2, 1);
>
> Multi-column foreign keys where one column is NULL effectively disable
> the FK, this is not specific to partitioned tables. They works as
> designed, but best avoid them.
>
> Christoph
>
Commits
Same data as JSON:
GET /api/v1/messages/:b64id/commits
the thread's linked commits as JSON, with link sources.
API reference →
-
Handle self-referencing FKs correctly in partitioned tables
- f51ae3187472 17.5 landed
- c83a38758d2a 18.0 landed
- b3a9c536db67 13.21 landed
- 6ba979cf570c 15.13 landed
- 1817d62ecbf5 16.9 landed
- 1649d153a172 14.18 landed
-
Restructure foreign key handling code for ATTACH/DETACH
- 5914a22f6ea5 17.1 cited
-
Fix self-referencing foreign keys with partitioned tables
- 614a406b4ff1 16.0 cited