Message-ID: <053b43a9f80793a8f31467ba9de3db90518ab120.camel@j-davis.com>
Subject: Re: pgsql: Fix search_path to a safe value during maintenance
 operations.
From: Jeff Davis <pgsql@j-davis.com>
To: Jeff Davis <jdavis@postgresql.org>, pgsql-committers@lists.postgresql.org
Date: Fri, 09 Jun 2023 17:49:00 -0700
In-Reply-To: <d20864b929ff769a0ebf772359719f05bb6982cd.camel@j-davis.com>
References: <E1q7j7Y-000z1H-Hr@gemulon.postgresql.org>
	 <89a415b86d5421941e4281ba5bf6288934078624.camel@j-davis.com>
	 <d20864b929ff769a0ebf772359719f05bb6982cd.camel@j-davis.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
User-Agent: Evolution 3.44.4-0ubuntu1 
MIME-Version: 1.0
Archived-At: <https://www.postgresql.org/message-id/053b43a9f80793a8f31467ba9de3db90518ab120.camel%40j-davis.com>
Precedence: bulk

On Fri, 2023-06-09 at 17:37 -0700, Jeff Davis wrote:
> Attached a patch to mark those functions as PARALLEL UNSAFE, which
> fixes the problem.

On second thought, that might not be acceptable for amcheck, depending
on how its run.

I think it's OK if run by pg_amcheck, because that runs it on a single
index at a time in each connection, and parallelizes by opening more
connections.

But if some users are calling the check functions across many tables in
a single select statement (e.g. in the targetlist of a query on
pg_class), then they'll experience a regression.

> Alternatively, I could just take out that line, as those SQL
> functions
> are not controlled by the MAINTAIN privilege. But for consistency I
> think it's a good idea to leave it in so that index functions are
> called with the right search path for amcheck.

If marking them PARALLEL UNSAFE is not acceptable, then this seems like
a fine solution.

Regards,
	Jeff Davis