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help / color / mirror / Atom feedFrom: Radoulov, Dimitre <cichomitiko@gmail.com>
To: Laurenz Albe <laurenz.albe@cybertec.at>
Cc: pgsql-docs@lists.postgresql.org
Subject: Re: Documentation clarification request: pg_dumpall and Large Objects
Date: Thu, 4 Dec 2025 18:12:53 +0100
Message-ID: <CAGJBphS4TLNvAyNcWj_NSfer9SoDzco35apkT+8-wqXCthSK6w@mail.gmail.com> (raw)
In-Reply-To: <d4ab85597252c7a529f64ffd5cc5b09d92504df4.camel@cybertec.at>
References: <CAGJBphSX2oMPPu=VM4U8NP4+qffFH_483tFQCJ_s-mOcN3DLDw@mail.gmail.com>
<d4ab85597252c7a529f64ffd5cc5b09d92504df4.camel@cybertec.at>
Il Gio 4 Dic 2025, 16:50 Laurenz Albe <laurenz.albe@cybertec.at> ha scritto:
> 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.
> >
> > This behavior is clear from the implementation, but not from the
> > documentation.
> >
> > I propose adding an explicit note such as:
> >
> > "pg_dumpall does not include Large Objects (BLOBs). To back up
> > Large 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 (“dumping”) all PostgreSQL
> 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
> specified.
>
> Since pg_dumpall dumps the databases (and not parts of the databases), it
> will
> automatically dump large objects too.
>
> But I admit that you have to go by circumstantial evidence here. But
> rather
> than explicitly naming large objects, perhaps it would be useful to add
> something
> 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
> parameters
> changed with ALTER SYSTEM.
>
Thank you for the clarification.
I believe the confusion comes from the historical behavior of pg_dump in
older PostgreSQL versions.
Since pg_dumpall delegates to pg_dump, and pg_dump’s default behavior has
included LOBs since 7.1, the current behavior is consistent with your
explanation.
Thank you again for your time and for considering the suggestion.
Best regards
Dimitre
>
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To: pgsql-docs@postgresql.org
Cc: cichomitiko@gmail.com, laurenz.albe@cybertec.at, pgsql-docs@lists.postgresql.org
Subject: Re: Documentation clarification request: pg_dumpall and Large Objects
In-Reply-To: <CAGJBphS4TLNvAyNcWj_NSfer9SoDzco35apkT+8-wqXCthSK6w@mail.gmail.com>
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