Message-ID: <8cb047c8327ca195c635460e4e509d69a4bad3ed.camel@cybertec.at>
Subject: Re: last_analyze/last_vacuum in pg_stat_all_tables (PG 17.10)
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Thomas Michael Engelke <thomas.engelke@posteo.de>,
 "pgsql-general@lists.postgresql.org"
	 <pgsql-general@lists.postgresql.org>
Date: Sun, 05 Jul 2026 15:12:57 +0200
In-Reply-To: <a21fd458be8ac8edc342f9a8e145739a1f435884.camel@posteo.de>
References: <a21fd458be8ac8edc342f9a8e145739a1f435884.camel@posteo.de>
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On Fri, 2026-07-03 at 10:20 +0000, Thomas Michael Engelke wrote:
> What happens *sometimes* on servers is that the age of the oldest
> maintenance increases to infinity, as the fields of last_analyze and
> last_vacuum are emptied (NULL value).
>=20
> However, looking into the monitoring system I can see that there must
> have been values in these fields before. I can see the values coming
> ouf of that check 2 hours ago, the values were not infinity.
>=20
> Are there any circumstances under which these fields get emptied?

A crash of the database server would do that.

Also, if somebody calls pg_stat_reset() or
pg_stat_reset_single_table_counters('table_name'), that would reset
these counters.

Yours,
Laurenz Albe