Re: adding partitioned tables to publications

On Mon, Oct 7, 2019 at 9:55 AM Amit Langote <amitlangote09@gmail.com> wrote:
> One cannot currently add partitioned tables to a publication.
>
> create table p (a int, b int) partition by hash (a);
> create table p1 partition of p for values with (modulus 3, remainder 0);
> create table p2 partition of p for values with (modulus 3, remainder 1);
> create table p3 partition of p for values with (modulus 3, remainder 2);
>
> create publication publish_p for table p;
> ERROR:  "p" is a partitioned table
> DETAIL:  Adding partitioned tables to publications is not supported.
> HINT:  You can add the table partitions individually.
>
> One can do this instead:
>
> create publication publish_p1 for table p1;
> create publication publish_p2 for table p2;
> create publication publish_p3 for table p3;
>
> but maybe that's too much code to maintain for users.
>
> I propose that we make this command:
>
> create publication publish_p for table p;
>
> automatically add all the partitions to the publication.  Also, any
> future partitions should also be automatically added to the
> publication.  So, publishing a partitioned table automatically
> publishes all of its existing and future partitions.  Attached patch
> implements that.
>
> What doesn't change with this patch is that the partitions on the
> subscription side still have to match one-to-one with the partitions
> on the publication side, because the changes are still replicated as
> being made to the individual partitions, not as the changes to the
> root partitioned table.  It might be useful to implement that
> functionality on the publication side, because it allows users to
> define the replication target any way they need to, but this patch
> doesn't implement that.

Added this to the next CF: https://commitfest.postgresql.org/25/2301/