RE: Added schema level support for publication.

On Thursday, July 22, 2021 1:30 AM vignesh C <vignesh21(at)gmail(dot)com> wrote:
>
> Thanks for reporting this issue, this issue is fixed in the attached v13 patch.
> I have changed relation name pg_publication_schema to
> pg_publication_sch so that the names are in similar lines with
> pg_publication_rel relation and similar changes were done for variable
> names too.

Thanks for your fixing. The issue is fixed as you said.

After applying your V13 patch. I noticed that if I specify duplicate schema names when using "ALTER PUBLICATION ... SET SCHEMA ...", I would get the following error message:

postgres=# ALTER PUBLICATION pub1 SET SCHEMA s1,s1;
ERROR: duplicate key value violates unique constraint "pg_publication_sch_psnspcid_pspubid_index"
DETAIL: Key (psnspcid, pspubid)=(16406, 16405) already exists.

I think the error message is pretty hard to understand. Maybe we can do sth to improve this scenario.

Here is two proposal:
1. Don't report error message, just add some code to make the above command to be executed successfully,
just like "ALTER PUBLICATION ... SET TABLE ..." as follolws:

postgres=# ALTER PUBLICATION pub2 SET TABLE t1,t1;
ALTER PUBLICATION
postgres=# \dRp+ pub2
Publication pub2
Owner | All tables | Inserts | Updates | Deletes | Truncates | Via root | Pubtype
----------+------------+---------+---------+---------+-----------+----------+---------
postgres | f | t | t | t | t | f | t
Tables:
"public.t1"

2. Report a easily understandable message like: Schema s1 specified more than once

Thoughts?

Regards
Tang