On Wed, Mar 18, 2026 at 6:56 AM Amit Kapila <amit.kapila16@gmail.com> wrote:
>
> On Tue, Mar 10, 2026 at 3:40 AM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
> >
> > On Tue, Mar 3, 2026 at 2:22 AM Zhijie Hou (Fujitsu)
> > <houzj.fnst@fujitsu.com> wrote:
> > >
> > > On Saturday, February 28, 2026 7:48 AM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
> > > > To: Marcos Pegoraro <marcos@f10.com.br>
> > > > Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
> > > > Subject: Re: Initial COPY of Logical Replication is too slow
> > > >
> > > > Another variant of this approach is to extend
> > > > pg_get_publication_table() so that it can accept a relid to get the publication
> > > > information of the specific table. I've attached the patch for this idea. I'm
> > > > going to add regression test cases.
> > > >
> > > > pg_get_publication_table() is a VARIACID array function so the patch changes
> > > > its signature to {text[] [, oid]}, breaking the tool compatibility. Given this
> > > > function is mostly an internal-use function (we don't have the documentation
> > > > for it), it would probably be okay with it. I find it's clearer than the other
> > > > approach of introducing pg_get_publication_table_info(). Feedback is very
> > > > welcome.
> > >
> > > Thanks for updating the patch.
> > >
> > > I have few comments for the function change:
> > >
> > > 1.
> > >
> > > If we change the function signature, will it affect use cases where the
> > > publisher version is newer and the subscriber version is older ? E.g., when
> > > publisher is passing text style publication name to pg_get_publication_tables().
> >
> > Good point.
> >
> > I noticed that changing the function signature of
> > pg_get_publication_tables() breaks logical replication setups where
> > the subscriber is 18 or older.
> >
>
> Why adding a new function with additional parameters (Oid relid)
> couldn't help with such a case? I am asking because your previous
> version code looks simpler as compared to the new patch version.
I tried to pass a relid to pg_get_publication_tables() but we cannot
avoid changing its signature because it's a VARIADIC array function.
The previous patch changed pg_get_publication_tables(VARIADIC text[])
to pg_get_publication_tables(text[] {, relid}). However, changing the
function signature would break the logical replication from v19 to an
older version.
Regards,
--
Masahiko Sawada
Amazon Web Services: https://aws.amazon.com
