Обсуждение: Disallow concurrent ALTER DOMAIN and DROP DOMAIN

Поиск
Список
Период
Сортировка

Disallow concurrent ALTER DOMAIN and DROP DOMAIN

От
jian he
Дата:
hi

similar to thread "Prevent internal error at concurrent CREATE OR
REPLACE FUNCTION"
[1].

We should prevent concurrent modifications to a domain's definition. Currently,
it is possible for one session to drop a domain while another session
simultaneously adds a constraint to it.
It may result in errors such as "tuple concurrently updated."

also dropping a domain should not be allowed if another session is
modifying it, IMHO.

The attached patch is very similar to the "CREATE OR REPLACE FUNCTION"
thread [1],
by acquiring a AccessExclusiveLock on the changed domain oid.
Other sessions must wait for the current transactions to finish
modifying the domain definition
before making changes on it.

[1] https://postgr.es/m/20250331200057.00a62760966a821d484ea904@sraoss.co.jp

Вложения

Re: Disallow concurrent ALTER DOMAIN and DROP DOMAIN

От
Andres Freund
Дата:
Hi,

On 2025-05-23 21:19:07 +0800, jian he wrote:
> similar to thread "Prevent internal error at concurrent CREATE OR
> REPLACE FUNCTION"
> [1].
> 
> We should prevent concurrent modifications to a domain's definition. Currently,
> it is possible for one session to drop a domain while another session
> simultaneously adds a constraint to it.
> It may result in errors such as "tuple concurrently updated."
> 
> also dropping a domain should not be allowed if another session is
> modifying it, IMHO.
> 
> The attached patch is very similar to the "CREATE OR REPLACE FUNCTION"
> thread [1],
> by acquiring a AccessExclusiveLock on the changed domain oid.
> Other sessions must wait for the current transactions to finish
> modifying the domain definition
> before making changes on it.

I don't know if this is still an active patch - if it is, it'd be good to fix
CI:
https://cirrus-ci.com/github/postgresql-cfbot/postgresql/cf%2F5773
it doesn't build.

If it's not current anymore, please close the CI entry.

Greetings,

Andres