Message-ID: <5d0349511403954daf7578bdab2271a55ddb3395.camel@cybertec.at>
Subject: Re: Further clarification in documentation: No deletion of
 unreferenced large objects
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: oliver_schmidt_@hotmail.de, pgsql-docs@lists.postgresql.org
Date: Mon, 12 Jun 2023 18:48:54 +0200
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On Mon, 2023-06-12 at 13:48 +0000, PG Doc comments form wrote:
> Page: https://www.postgresql.org/docs/15/datatype-binary.html
>=20
> When deleting a row that references (contains) a large object, I think th=
at
> most users expect the DBMS to take care of the, now unreferenced, BLOB. I=
t's
> good to know that PostgreSQL handles this differently and that one must
> periodically use vacuumlo to avoid BLOB data piling up. At least, that's
> what I understood.
>=20
> I think a small paragraph in the documentation about this would help many
> people. I can help with writing, if needed.

This is documented here:

https://www.postgresql.org/docs/current/lo.html

Admittedly, that is not the best place.  Perhaps the introductory chapter
in https://www.postgresql.org/docs/current/lo-intro.html would be a good
place to mention that there is no referential integrity to large objects.

Yours,
Laurenz Albe