RE: Added schema level support for publication. - Mailing list pgsql-hackers

From tanghy.fnst@fujitsu.com
Subject RE: Added schema level support for publication.
Date
Msg-id OS0PR01MB6113A758B3EE942937F39D29FBE59@OS0PR01MB6113.jpnprd01.prod.outlook.com
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In response to Re: Added schema level support for publication.  (vignesh C <vignesh21@gmail.com>)
Responses Re: Added schema level support for publication.  (Greg Nancarrow <gregn4422@gmail.com>)
Re: Added schema level support for publication.  (vignesh C <vignesh21@gmail.com>)
List pgsql-hackers
On Thursday, July 22, 2021 1:30 AM vignesh C <vignesh21@gmail.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

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