Thread

Re: Support EXCEPT for ALL SEQUENCES publications

Shlok Kyal <shlok.kyal.oss@gmail.com> — 2026-05-29T11:59:11Z

Hi Zsolt,
Thanks for reviewing the patch.

On Thu, 28 May 2026 at 03:22, Zsolt Parragi <zsolt.parragi@percona.com> wrote:
>
> Hello!
>
> +                                       if (footers[0] == NULL)
> +                                               footers[0] = pg_strdup(tmpbuf.data);
> +                                       else if (footers[1] == NULL)
> +                                               footers[1] = pg_strdup(tmpbuf.data);
> +                                       else
> +                                               footers[2] = pg_strdup(tmpbuf.data);
> +                                       resetPQExpBuffer(&tmpbuf);
>
> Shouldn't the matching free calls also updated, this now leaks footers[2]?
>
Yes, correct. Made the change for the same.

> +                                                         "\n AND NOT EXISTS (\n"
> +                                                         "     SELECT 1\n"
> +                                                         "     FROM pg_catalog.pg_publication_rel pr\n"
> +                                                         "     WHERE pr.prpubid = p.oid AND\n"
> +                                                         "     pr.prrelid = '%s')"
>
> Isn't a pr.prexcept check missing from this? It is included in other queries.
>
pg_publication_rel has an entry for table/sequence if we specifically
include/exclude it in a publication.
So, we can say, pg_publication_rel contains an entry for a
Table/Sequence for a ALL TABLES/ ALL SEQUENCE publication, only if it
is specified in the EXCEPT clause.
So, the above query will give the expected results even if we donot
use the ' pr.prexcept' flag.

For the case: _("Get publications that publish this table"))
Here as well we use a similar query without prexcept:
"WHERE p.puballtables AND pg_catalog.pg_relation_is_publishable('%s')\n"
                                      "     AND NOT EXISTS (\n"
                                      "     SELECT 1\n"
                                      "     FROM
pg_catalog.pg_publication_rel pr\n"
                                      "     WHERE pr.prpubid = p.oid AND\n"
                                      "     (pr.prrelid = '%s' OR
pr.prrelid = pg_catalog.pg_partition_root('%s')))\n"
                                      "ORDER BY 1;",


> -               /* EXCEPT clause is not supported with ALTER PUBLICATION */
> -               Assert(exceptseqs == NIL);
> -
>
> Would it be worth it to keep a more restricted assert, saying that
> EXCEPT clause is only supported for ALTER PUBLICATION ... SET?
>
>
Added the Assert in 0002 patch.

I have addressed the comments and attached the v8 patch.

Thanks,
Shlok Kyal