From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Justin Pryzby <pryzby@telsasoft.com>, Tomas Vondra <tv@fuzzy.cz>,
        Dean Rasheed <dean.a.rasheed@gmail.com>, pgsql-hackers@postgresql.org
Subject: Re: ANALYZE: ERROR: tuple already updated by self
In-reply-to: <20190619000837.awy6j7h45ahd4vop@alap3.anarazel.de>
References: <20190618231233.GA27470@telsasoft.com>
 <20190618234858.GK16019@telsasoft.com>
 <20190619000837.awy6j7h45ahd4vop@alap3.anarazel.de>
Comments: In-reply-to Andres Freund <andres@anarazel.de>
	message dated "Tue, 18 Jun 2019 17:08:37 -0700"
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <30098.1560903410.1@sss.pgh.pa.us>
Date: Tue, 18 Jun 2019 20:16:50 -0400
Message-ID: <30099.1560903410@sss.pgh.pa.us>
Precedence: bulk

Andres Freund <andres@anarazel.de> writes:
> I think the problem is pretty plainly that for inheritance tables we'll
> try to store extended statistics twice. And thus end up updating the
> same row twice.

They shouldn't be the same row though.  If we're to try to capture
ext-stats on inheritance trees --- and I think that's likely a good
idea --- then we need a bool corresponding to pg_statistic's stainherit
as part of pg_statistic_ext's primary key.

Since there is no such bool there now, and I assume that nobody wants
yet another pg_statistic_ext-driven catversion bump for v12, the only
fix is to get the stats machinery to not compute or store such stats.
For now.  But I think we ought to change that in v13.

			regards, tom lane