Message-ID: <d4ab85597252c7a529f64ffd5cc5b09d92504df4.camel@cybertec.at>
Subject: Re: Documentation clarification request: pg_dumpall and Large
 Objects
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: "Radoulov, Dimitre" <cichomitiko@gmail.com>,
	pgsql-docs@lists.postgresql.org
Date: Thu, 04 Dec 2025 16:50:55 +0100
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On Thu, 2025-12-04 at 13:12 +0100, Radoulov, Dimitre wrote:
> I would like to request a clarification in the pg_dumpall
> documentation regarding Large Objects (LOBs). The current
> documentation does not explicitly state whether pg_dumpall includes
> Large Objects in its output.
>=20
> This behavior is clear from the implementation, but not from the
> documentation.
>=20
> I propose adding an explicit note such as:
>=20
> =C2=A0 "pg_dumpall does not include Large Objects (BLOBs). To back up
> =C2=A0 =C2=A0Large Objects, use pg_dump -b per database."

At the beginning of the "pg_dumpall" page we see:

  pg_dumpall is a utility for writing out (=E2=80=9Cdumping=E2=80=9D) all P=
ostgreSQL databases
  of a cluster into one script file. [...].
  It does this by calling pg_dump for each database in the cluster.

And the pg_dump documentation says:

  -b
  --large-objects
  --blobs (deprecated)

    Include large objects in the dump. This is the default behavior except =
when
    --schema, --table, --schema-only, --statistics-only, or --no-data is sp=
ecified.

Since pg_dumpall dumps the databases (and not parts of the databases), it w=
ill
automatically dump large objects too.

But I admit that you have to go by circumstantial evidence here.  But rathe=
r
than explicitly naming large objects, perhaps it would be useful to add som=
ething
like

  pg_dumpall is primarily intended as a tool to upgrade database clusters.
  As such, it by default exports all data of the entire cluster.
  The only part of the state of a database cluster that is *not* included
  in the output of pg_dumpall are the configuration files and database para=
meters
  changed with ALTER SYSTEM.

Yours,
Laurenz Albe