Re: Feature Request - DDL deployment with logical replication

On Fri, Mar 30, 2018 at 10:16 AM, Peter Eisentraut <
peter(dot)eisentraut(at)2ndquadrant(dot)com> wrote:

> On 3/29/18 13:21, Jeremy Finzel wrote:
> > Although we are thrilled with some of the features already in logical
> > replication, this missing feature is the #1 reason that we don't plan to
> > take a serious look at built-in logical replication even for pg11,
> > because we have been able to use pglogical with our own extension
> > pgl_ddl_deploy in order to broadly deploy logical replication without
> > serious overhauls to our SDLC process, having schema changes managed
> > well. We really want a mechanism to put through DDL changes at the same
> > transactional point on the subscribers as we do on the publishers, which
> > also answers any complexities around deploying master-first or
> > slave-first in some interesting cases.
> >
> > Is there any particular vision for how the community might address this
> > need in the future?
>
> I think nobody has completely figured this out yet. Whatever is in
> pglogical and bdr and similar external projects are the best current
> compromises. But they have lots of problems, so I don't know if anyone
> is ready to propose something for in core yet.
>
> --
> Peter Eisentraut http://www.2ndQuadrant.com/
> PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
>

IMO, it would be an acceptable and good first step to provide a function
that will replicate a SQL command through the replication stream at the
right point, even if there is still no automation around it.