From: Tom Lane <tgl@sss.pgh.pa.us>
To: Corey Huinker <corey.huinker@gmail.com>
cc: Magnus Hagander <magnus@hagander.net>, Jeff Davis <pgsql@j-davis.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>
Subject: Re: Statistics Import and Export
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Comments: In-reply-to Corey Huinker <corey.huinker@gmail.com>
	message dated "Sun, 31 Mar 2024 07:17:26 -0400"
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Date: Sun, 31 Mar 2024 14:41:00 -0400
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Corey Huinker <corey.huinker@gmail.com> writes:
> Having given this some thought, I'd be inclined to create a view,
> pg_stats_missing, with the same security barrier as pg_stats, but looking
> for tables that lack stats on at least one column, or lack stats on an
> extended statistics object.

The week before feature freeze is no time to be designing something
like that, unless you've abandoned all hope of getting this into v17.

There's a bigger issue though: AFAICS this patch set does nothing
about dumping extended statistics.  I surely don't want to hold up
the patch insisting that that has to happen before we can commit the
functionality proposed here.  But we cannot rip out pg_upgrade's
support for post-upgrade ANALYZE processing before we do something
about extended statistics, and that means it's premature to be
designing any changes to how that works.  So I'd set that whole
topic on the back burner.

It's possible that we could drop the analyze-in-stages recommendation,
figuring that this functionality will get people to the
able-to-limp-along level immediately and that all that is needed is a
single mop-up ANALYZE pass.  But I think we should leave that till we
have a bit more than zero field experience with this feature.

			regards, tom lane