Message-ID: <51fca6b6c0032d28e053ad89f7e858e2a9e498af.camel@j-davis.com>
Subject: Re: Statistics Import and Export
From: Jeff Davis <pgsql@j-davis.com>
To: Corey Huinker <corey.huinker@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andres Freund <andres@anarazel.de>, Michael Paquier
 <michael@paquier.xyz>,  jian he <jian.universality@gmail.com>, Nathan
 Bossart <nathandbossart@gmail.com>, Bruce Momjian <bruce@momjian.us>,
 Matthias van de Meent <boekewurm+postgres@gmail.com>,  Magnus Hagander
 <magnus@hagander.net>, Stephen Frost <sfrost@snowman.net>, Ashutosh Bapat
 <ashutosh.bapat.oss@gmail.com>, Peter Smith <smithpb2250@gmail.com>, 
 PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
 alvherre@alvh.no-ip.org
Date: Wed, 26 Feb 2025 10:02:13 -0800
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On Wed, 2025-02-26 at 04:25 -0500, Corey Huinker wrote:
> 0001 - Add attnum support to=C2=A0attribute_statistics_update
>=20
> * Basically what Tom posted earlier, minus the pg_set_attribute_stats
> stuff, obviously.

Should have a couple simple tests.

And I would use two different error message wordings:

  "must specify either attname or attnum"
  "cannot specify both attname and attnum"

(or similar)

The "one of attname and attnum" is a bit awkward.

The new struct for pg_clear_attribute_stats() isn't great, but as
discussed we can get rid of that in a subsequent commit.

Otherwise LGTM.

> 0002 - Add attnum support to pg_dump.
>=20
> * Removed=C2=A0att_stats_arginfo
> * Folds=C2=A0appendRelStatsImport and=C2=A0appendAttStatsImport
> into=C2=A0dumpRelationStats=C2=A0

Can we add a test here, too, to check that tables dump the attname and
indexes dump the attnum?

Everything else in the file uses i_fieldname =3D PQfnumber(), but in this
patch you're just using raw numbers.

Some of the fields from pg_stats are NOT NULL, so we could consider
issuing a warning in that case rather than just skipping it.

And it could use a pgindent.

I ran a quick measurement and it appears within the noise of the
numbers I posted here:

https://www.postgresql.org/message-id/6af48508a32499a8be3398cafffd29fb6188c=
44b.camel@j-davis.com

Regards,
	Jeff Davis