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: pgsql-bugs@lists.postgresql.org
Date: 2025-04-01T09:06:13Z
Lists: pgsql-bugs, pgsql-hackers
As mentioned at
https://www.postgresql.org/message-id/18156-a44bc7096f0683e6%40postgresql.org
this is a regression introduced in version 15.X and still present in 17.4.

I'm running the postgres:17.4-alpine docker official image.

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REPRO
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drop table if exists test;

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);

create table test_1 partition of test for values in (1);
create table test_9 partition of test for values in (9);

insert into test values (1, 1, null), (1, 2, 1);

-- doesn't trigger an error
-- delete from test where (id_1, id_2) = (1, 1);

-- doesn't trigger an error
-- update test set id_1 = 9 where (id_1, id_2) = (1, 1);

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Both deletion and update runs smoothly.
Also, potential cascade delete and cascade update rules are ignored.

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Handle self-referencing FKs correctly in partitioned tables

  2. Restructure foreign key handling code for ATTACH/DETACH

  3. Fix self-referencing foreign keys with partitioned tables