Horton

Re: Skipping schema changes in publication

Peter Smith <smithpb2250@gmail.com>

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From: Peter Smith <smithpb2250@gmail.com>
To: Amit Kapila <amit.kapila16@gmail.com>
Cc: vignesh C <vignesh21@gmail.com>, Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2022-05-17T04:29:33Z
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. Fix miscellaneous issues in EXCEPT publication clause.

  2. Change syntax of EXCEPT TABLE clause in publication commands.

  3. Add support for EXCEPT TABLE in ALTER PUBLICATION.

  4. Allow table exclusions in publications via EXCEPT TABLE.

  5. Add wait_for_subscription_sync for TAP tests.

On Tue, May 17, 2022 at 1:56 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
>
> On Tue, May 17, 2022 at 7:35 AM Peter Smith <smithpb2250@gmail.com> wrote:
> >
> > Below are my review comments for v5-0002.
> >
> > There may be an overlap with comments recently posted by Osumi-san [1].
> >
> > (I also have review comments for v5-0002; will post them tomorrow)
> >
> > ======
> >
> > 1. General
> >
> > Is it really necessary to have to say "EXCEPT TABLE" instead of just
> > "EXCEPT". It seems unnecessarily verbose and redundant when you write
> > "FOR ALL TABLES EXCEPT TABLE...".
> >
> > If you want to keep this TABLE keyword (maybe you have plans for other
> > kinds of except?)
> >
>
> I don't think there is an immediate plan but one can imagine using
> EXCEPT SCHEMA. Then for column lists, one may want to use the syntax
> Create Publication pub1 For Table t1 Except Cols (c1, ..);
>
> > then IMO perhaps at least it can be the optional
> > default except type. e.g. EXCEPT [TABLE].
> >
>
> Yeah, that might be okay, so, even if we plan to extend this in the
> future, by default we will consider the list of tables after EXCEPT
> but if the user mentions EXCEPT SCHEMA or something else then we can
> use a different object. Is that sound okay?

Yes. That is what I meant.

>
> >
> > 3. General
> >
> > The ONLY keyword seems supported by the syntax for tables of the
> > except-list (more on this in later comments) but:
> > a) I am not sure if the patch code is accounting for that, and
> > b) There are no test cases using ONLY.
> >
> > ~~~
> >
>
> Isn't it better to map ONLY with the way it can already be specified
> in CREATE PUBLICATION? I am not sure what exactly is proposed and what
> is your suggestion? Can you please explain if it is different from the
> way we use it for CREATE PUBLICATION?
>

Yes, I am not proposing anything different to how ONLY already works
for published tables. I was only questioning whether the patch behaves
correctly when ONLY is specified for the tables of the EXCEPT list. I
had some doubt about it because there are a few other review comments
I wrote (e.g. in pg_dump.c),  and also I did not find any ONLY tests,

------
Kind Regards,
Peter Smith.
Fujitsu Australia