Date: Tue, 8 Apr 2025 15:25:07 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Amit Kapila <amit.kapila16@gmail.com>
Cc: Michael Paquier <michael@paquier.xyz>,
	Alexander Lakhin <exclusion@gmail.com>,
	Tom Lane <tgl@sss.pgh.pa.us>,
	"Jonathan S. Katz" <jkatz@postgresql.org>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Large expressions in indexes can't be stored (non-TOASTable)
Message-ID: <Z_WGI4cKoTjhUXrs@nathan>
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On Tue, Apr 08, 2025 at 04:44:02PM +0530, Amit Kapila wrote:
> On Fri, Apr 4, 2025 at 7:58 PM Nathan Bossart <nathandbossart@gmail.com> wrote:
>> On Fri, Apr 04, 2025 at 05:16:43PM +0530, Amit Kapila wrote:
>> > Can we dodge adding this push call if we restrict the length of the
>> > origin name to some reasonable limit like 256 or 512 and avoid the
>> > need of toast altogether?
>>
>> We did consider just removing pg_replication_origin's TOAST table earlier
>> [0], but we decided against it at that time.  Maybe it's worth
>> reconsidering...
> 
> I don't see any good reason in that email for not removing the TOAST
> table for pg_replication_origin. I would prefer to remove it rather
> than add protection related to its access.

The only reason I can think of is that folks might have existing
replication origins with extremely long names that would cause upgrades to
fail.  While I think it would be probably be okay to remove the TOAST table
and restrict origin names to 512 bytes (like we did for password hashes in
commit 8275325), folks routinely complain about NAMEDATALEN, so I think we
should be cautious here.

-- 
nathan