Horton

Re: Support logical replication of DDLs

Zheng Li <zhengli10@gmail.com>

View thread
From: Zheng Li <zhengli10@gmail.com>
To: Amit Kapila <amit.kapila16@gmail.com>
Cc: Alvaro Herrera <alvherre@alvh.no-ip.org>, Peter Smith <smithpb2250@gmail.com>, Ajin Cherian <itsajin@gmail.com>, vignesh C <vignesh21@gmail.com>, li jie <ggysxcq@gmail.com>, Dilip Kumar <dilipbalaut@gmail.com>, "houzj.fnst@fujitsu.com" <houzj.fnst@fujitsu.com>, Masahiko Sawada <sawada.mshk@gmail.com>, Japin Li <japinli@hotmail.com>, rajesh singarapu <rajesh.rs0541@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2023-02-17T04:13:09Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Add a run_as_owner option to subscriptions.

  2. Refactor pgoutput_change().

  3. Print the correct aliases for DML target tables in ruleutils.

  4. Fix object identity string for transforms

  5. Add grantable MAINTAIN privilege and pg_maintain role.

  6. Get rid of recursion-marker values in enum AlterTableType

  7. Release cache tuple when no longer needed

  8. Empty search_path in logical replication apply worker and walsender.

  9. Refactor format_type APIs to be more modular

  10. Use wrappers of PG_DETOAST_DATUM_PACKED() more.

> > I've implemented a prototype to allow replicated objects to have the
> > same owner from the publisher in
> > v69-0008-Allow-replicated-objects-to-have-the-same-owner-from.patch.
> >
>
> I also think it would be a helpful addition for users.A few points
Thanks for supporting this addition.

> that come to my mind are: (a) Shouldn't the role have the same
> privileges (for ex. rolbypassrls or rolsuper) on both sides before we
> allow this? (b) Isn't it better to first have a replication of roles?

> I think if we have (b) then it would be probably a bit easier because
> if the subscription has allowed replicating roles and we can confirm
> that the role is replicated then we don't need to worry about the
> differences.

Yes, having role replication will help further reduce the manual
effort. But even if we don't end up doing role replication soon, I
think we can still provide this subscription option (match_ddl_owner,
off by default) and document that the same roles need to be on both
sides for it to work.

> Now, coming to implementation, won't it be better if we avoid sending
> the owner to the subscriber unless it is changed for the replicated
> command? Consider the current case of tables where we send schema only
> if it is changed. This is not a direct mapping but it would be better
> to avoid sending additional information and then process it on the
> subscriber for each command.

Right, we can do some optimization here: only send the owner for
commands that create objects (CREATE TABLE/FUNCTION/INDEX etc.) Note
that ALTER TABLE/OBJECT OWNER TO is replicated so we don't need to
worry about owner change.

Regards,
Zane