Date: Tue, 18 Jun 2019 18:12:33 -0500
From: Justin Pryzby <pryzby@telsasoft.com>
To: pgsql-hackers@postgresql.org
Subject: ANALYZE: ERROR:  tuple already updated by self
Message-ID: <20190618231233.GA27470@telsasoft.com>
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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

The issue goes away if I drop the stats object and comes back if I recreate it.

We're running 11.3 ; most of the (very few) reports from this error are from
almost 10+ years ago, running pg7.3 like.

I've taken a couple steps to resolve the issue (vacuum full and then reindex
pg_statistic and its toast and the target table, which doesn't have a toast).

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.

Does anyone want debugging/diagnostic info before I do that ?

Justin