Feedback-ID: ia2694551:Fastmail
Date: Tue, 7 Apr 2026 14:33:50 +0200
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Amit Kapila <amit.kapila16@gmail.com>
Cc: Mihail Nikalayeu <mihailnikalayeu@gmail.com>,
	Antonin Houska <ah@cybertec.at>,
 Srinath Reddy Sadipiralla <srinath2133@gmail.com>,
	Matthias van de Meent <boekewurm+postgres@gmail.com>,
 Pg Hackers <pgsql-hackers@lists.postgresql.org>,
	Robert Treat <rob@xzilla.net>
Subject: Re: Adding REPACK [concurrently]
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On 2026-Apr-07, Amit Kapila wrote:

> I have a question based on 0001's commit message: "This patch adds a
> new option to logical replication output plugin, to declare that it
> does not use shared catalogs (i.e. catalogs that can be changed by
> transactions running in other databases in the cluster).". In which
> cases, currently plugin needs to access multi-database transactions or
> transactions that need to access shared catalogs and on what basis a
> plugin can decide that the changes it requires won't need any such
> access.

I don't think any plugin needs "multi-database" access as such, but
needing access to shared catalogs is likely normal.  Repack knows it
won't access any shared catalogs, so it can set the flag at ease.

There's a cross-check added in the commit that tests for access to
shared catalogs if the flag is set to false.  I guess you could set it
to false and see what breaks :-)

-- 
Álvaro Herrera        Breisgau, Deutschland  —  https://www.EnterpriseDB.com/