Date: Tue, 18 Jun 2019 19:38:34 -0500
From: Justin Pryzby <pryzby@telsasoft.com>
To: pgsql-hackers@postgresql.org
Subject: Re: ANALYZE: ERROR:  tuple already updated by self
Message-ID: <20190619003834.GA11006@telsasoft.com>
References: <20190618231233.GA27470@telsasoft.com>
 <20190618234858.GK16019@telsasoft.com>
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On Tue, Jun 18, 2019 at 06:48:58PM -0500, Justin Pryzby wrote:
> On Tue, Jun 18, 2019 at 06:12:33PM -0500, Justin Pryzby wrote:
> > A customers DB crashed due to OOM.  While investigating the issue in our
> > report, I created MV stats, which causes this error:
> > 
> > ts=# CREATE STATISTICS sectors_stats (dependencies) ON site_id,sect_id FROM sectors;
> > CREATE STATISTICS
> > ts=# ANALYZE sectors;
> > ERROR:  XX000: tuple already updated by self
> > LOCATION:  simple_heap_update, heapam.c:4613
> 
> > I'm guessing the issue is with pg_statistic_ext, which I haven't touched.
> > 
> > Next step seems to be to truncate pg_statistic{,ext} and re-analyze the DB.
> 
> Confirmed the issue is there.
> 
> ts=# analyze sectors;
> ERROR:  tuple already updated by self
> ts=# begin; delete from pg_statistic_ext; analyze sectors;
> BEGIN
> DELETE 87
> ANALYZE

Why this works seems to me to be unexplained..

Justin