From: Ronan Dunklau <ronan.dunklau@aiven.io>
To: Ibrar Ahmed <ibrar.ahmad@gmail.com>,
 Amit Khandekar <amitdkhan.pg@gmail.com>, pgsql-hackers@lists.postgresql.org,
 "Drouvot, Bertrand" <bdrouvot@amazon.com>
Cc: Andres Freund <andres@anarazel.de>, fabriziomello@gmail.com,
 Alvaro Herrera <alvherre@2ndquadrant.com>,
 tushar <tushar.ahuja@enterprisedb.com>,
 "[pgdg] Robert Haas" <robertmhaas@gmail.com>,
 Rahila Syed <rahila.syed@2ndquadrant.com>,
 pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: Minimal logical decoding on standbys
Date: Mon, 02 Aug 2021 17:47:14 +0200
Message-ID: <7574277.rk4qtukel5@aivenronan>
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Le lundi 2 ao=FBt 2021, 17:31:46 CEST Drouvot, Bertrand a =E9crit :
> > I think the beahviour when dropping a database on the primary should be
> > documented, and proper procedures for handling it correctly should be
> > suggested.
> >=20
> > Something along the lines of:
> >=20
> > "If a database is dropped on the primary server, the logical replication
> > slot on the standby will be dropped as well. This means that you should
> > ensure that the client usually connected to this slot has had the
> > opportunity to stream the latest changes before the database is dropped=
=2E"
>=20
> I am not sure we should highlight this as part of this patch.
>=20
> I mean, the same would currently occur on a non standby if you drop a
> database that has a replication slot linked to it.

The way I see it, the main difference is that you drop an additional object=
 on=20
the standby, which doesn't exist and that you don't necessarily have any=20
knowledge of on the primary. As such, I thought it would be better to be=20
explicit about it to warn users of that possible case.


Regards,

=2D-
Ronan Dunklau