Message-ID: <32b72ef82aba2e54a1eaaab248197a47091d675c.camel@cybertec.at>
Subject: Re: promote a deferred standby without applying WALs
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: "Zwettler Markus (OIZ)" <Markus.Zwettler@zuerich.ch>,
	"pgsql-admin@lists.postgresql.org"
	 <pgsql-admin@lists.postgresql.org>
Date: Tue, 16 Jul 2024 10:40:55 +0200
In-Reply-To: 
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References: 
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On Tue, 2024-07-16 at 08:04 +0000, Zwettler Markus (OIZ) wrote:
> I have a standby database running 3 hours behind the primary (recovery_mi=
n_apply_delay =3D '3h').
> =C2=A0
> In case of a logical error on the primary I want to promote the standby d=
atabase which still has correct data.
> =C2=A0
> The standby should not apply any more WAL in that case.
> =C2=A0
> It seems that this can only be done manually:
> =C2=A0
> =C2=A0=C2=A0=C2=A01. pg_ctl stop
> =C2=A0=C2=A0=C2=A02. rm -rf standby.signal
> =C2=A0=C2=A0=C2=A03. set primary_conninfo =3D ''
> =C2=A0=C2=A0=C2=A04. pg_ctl start
> =C2=A0
> Is there no single command on this?

I don't think there is a single command.

I would just set "recovery_target_time" to the appropriate time and reload.

Perhaps this could be the single command:

  psql -c "ALTER SYSTEM SET recovery_target_time =3D '2024-07-16 12:00:00'"=
 -c "SELECT pg_reload_conf()"

Yours,
Laurenz Albe

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