Message-ID: <48ad7007c0bbca725847473fe410cdda5753c65d.camel@cybertec.at>
Subject: Re: [PATCH] Doc: clarify that pg_upgrade statistics transfer works
 cross-version
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Bruce Momjian <bruce@momjian.us>, Nikolay Samokhvalov <nik@postgres.ai>
Cc: pgsql-docs@lists.postgresql.org
Date: Tue, 24 Mar 2026 17:53:27 +0100
In-Reply-To: <acKoBql5eQWpQH4N@momjian.us>
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On Tue, 2026-03-24 at 11:04 -0400, Bruce Momjian wrote:
> On Tue, Mar 24, 2026 at 05:36:42AM -0700, Nikolay Samokhvalov wrote:
> > On Mon, Mar 23, 2026 at 23:59 Laurenz Albe <laurenz.albe@cybertec.at> w=
rote:
> > How about adding a simple remark, like
> >=20
> > --- a/doc/src/sgml/ref/pgupgrade.sgml
> > +++ b/doc/src/sgml/ref/pgupgrade.sgml
> > +=C2=A0 =C2=A0 =C2=A0Transferring optimizer statistics works regardless=
 of the old cluster's
> > +=C2=A0 =C2=A0 =C2=A0major version.
> >=20
> > That would work too -- my goal was just to resolve confusion.
>=20
> I was under the same impression --- that it only worked with upgrades
> _from_ PG 18 and later.  However, I can't find any documentation on this
> limitation, so why did so many think this was true?  I don't think
> adding anything to the docs is the right approach.

Bruce, you are confusing me.  Your first sentence suggests that you
(erroneously) thought that upgrading statistics only works when upgrading
*from* v18 or better.  But your last sentence suggests that you'd rather
not add anything to the documentation that could dispel that misconception.

Why?

Yours,
Laurenz Albe