public inbox for [email protected]  
help / color / mirror / Atom feed
From: David Geier <[email protected]>
To: Matthias van de Meent <[email protected]>
Cc: Heikki Linnakangas <[email protected]>
Cc: pgsql-hackers <[email protected]>
Subject: Re: Reduce build times of pg_trgm GIN indexes
Date: Fri, 23 Jan 2026 11:18:56 +0100
Message-ID: <[email protected]> (raw)
In-Reply-To: <CAEze2WiUL9idZBbuUN+MuWqr6DcPr_-C91E9MTx=H62Xx5fHaQ@mail.gmail.com>
References: <[email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>
	<CAEze2WiUL9idZBbuUN+MuWqr6DcPr_-C91E9MTx=H62Xx5fHaQ@mail.gmail.com>

Hi Matthias,

On 21.01.2026 21:50, Matthias van de Meent wrote:
> On Wed, 21 Jan 2026 at 16:45, David Geier <[email protected]> wrote:
>>
>> How do we usually go about such backwards-compatibility breaking
>> changes?
> 
> When it concerns a bug, we mention the change in the release notes
> with a warning to reindex affected indexes to be sure no known
> corruption remains. See e.g. the final entry in the PG18 release
> notes' migration section here:
> https://www.postgresql.org/docs/18/release-18.html#RELEASE-18-MIGRATION.
> 
>> Could we have pg_upgrade reindex all GIN indexes? Would that be
>> acceptable?
> 
> No. We'd handle this like any other collation/opclass fixes; we ask
> users to reindex their indexes in their own time after they've
> upgraded their cluster. Note that in this case it concerns an issue
> with just one GIN opclass, not all GIN indexes; so even if we were to
> address this in pg_upgrade it wouldn't be a correct choice to reindex
> every GIN index, as only a subset of those would be affected by this
> issue.
> 
> Generally speaking, pg_upgrade doesn't concern itself with the
> validity of the data structures that are described by the catalogs
> that it upgrades, it only concerns itself with that it correctly
> transcribes the catalogs from one version to another, and that the
> data files of the old cluster are transfered correctly without
> changes.

Thanks for the clarifications and the link to the release notes. That's
very helpful. Then I know how to move on and will update the patch
accordingly.

--
David Geier






view thread (31+ messages)  latest in thread

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: [email protected]
  Cc: [email protected], [email protected], [email protected]
  Subject: Re: Reduce build times of pg_trgm GIN indexes
  In-Reply-To: <[email protected]>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox