Message-ID: <cea2d432215847a1d5cef1422ad1b21814f3f73b.camel@j-davis.com>
Subject: Re: Statistics Import and Export
From: Jeff Davis <pgsql@j-davis.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Corey Huinker <corey.huinker@gmail.com>, Stephen Frost
 <sfrost@snowman.net>,  Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>,
 Matthias van de Meent <boekewurm+postgres@gmail.com>, Peter Smith
 <smithpb2250@gmail.com>, PostgreSQL Hackers
 <pgsql-hackers@lists.postgresql.org>,  Tomas Vondra
 <tomas.vondra@enterprisedb.com>
Date: Sat, 30 Mar 2024 10:29:43 -0700
In-Reply-To: <447200.1711819134@sss.pgh.pa.us>
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On Sat, 2024-03-30 at 13:18 -0400, Tom Lane wrote:
> Surely they are data, not schema.=C2=A0 It would make zero sense to
> restore
> them if you aren't restoring the data they describe.

The complexity is that pg_upgrade does create the data, but relies on a
schema-only dump. So we'd need to at least account for that somehow,
either with a separate stats-only dump, or make a special case in
binary upgrade mode that dumps schema+stats (and resolves the CREATE
INDEX issue).

> Maybe we need to revisit CREATE INDEX's behavior rather
> than assuming it's graven in stone?

Would there be a significant cost to just not doing that? Or are you
suggesting that we special-case the behavior, or turn it off during
restore with a GUC?

Regards,
	Jeff Davis