Re: RFC: logical publication via inheritance root?

On Sat, Apr 1, 2023 at 5:06 AM Jacob Champion <jchampion(at)timescale(dot)com> wrote:
>
> On Fri, Mar 31, 2023 at 3:17 PM Peter Smith <smithpb2250(at)gmail(dot)com> wrote:
>
> > Outside the scope of special TimescaleDB tables and the speculated
> > pg_partman old-style table migration, will this proposed new feature
> > have any other application? In other words, do you know if this
> > proposal will be of any benefit to the *normal* users who just have
> > native PostgreSQL inherited tables they want to replicate?
>
> I think it comes down to why an inheritance scheme was used. If it's
> because you want to group rows into named, queryable subsets (e.g. the
> "cities/capitals" example in the docs [1]), I don't think this has any
> utility, because I assume you'd want to replicate your subsets as-is.
>

I also think so and your idea to have a function like
pg_set_logical_root() seems to make the inheritance hierarchy behaves
as a declarative partitioning scheme for the purpose of logical
replication.

> But if it's because you've implemented a partitioning scheme of your
> own (the docs still list reasons you might want to [2], even today),
> and all you ever really do is interact with the root table, I think
> this feature will give you some of the same benefits that
> publish_via_partition_root gives native partition users. We're very
> much in that boat, but I don't know how many others are.
>

I agree that there may still be cases as pointed out by you where
people want to use inheritance as a mechanism for partitioning but I
feel those would still be in the minority. Personally, I am not very
excited about this idea.

--
With Regards,
Amit Kapila.