Message-ID: <b0991c2d8348da5b97bb0cdb1fe7a3d6a21a0df6.camel@cybertec.at>
Subject: Re: Performance implications of partitioning by UUIDv7 range in
 PostgreSQL v18
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: David Rowley <dgrowleyml@gmail.com>
Cc: Jonathan Reis <jon.reis@conevity.com>, Greg Sabino Mullane
	 <htamfids@gmail.com>, Olof Salberger <olof.salberger@gmail.com>,
	pgsql-performance@lists.postgresql.org
Date: Fri, 24 Oct 2025 08:04:16 +0300
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On Fri, 2025-10-24 at 11:54 +1300, David Rowley wrote:
> On Fri, 24 Oct 2025 at 09:38, Laurenz Albe <laurenz.albe@cybertec.at> wro=
te:
> > I recommend that you create a primary key on each partition rather than=
 having one
> > on the partitioned table.
>=20
> It might be worth mentioning that doing that would forego having the
> ability to reference the partitioned table in a foreign key
> constraint.

Right, but referencing a partitioned table with a foreign key is a mixed bl=
essing
anyway: you could no longer drop partitions from the partitioned table with=
out
scanning the referencing table to verify that the foreign key is not violat=
ed.

Yours,
Laurenz Albe