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  1. Doc: clarify introductory description of pg_dumpall.

  2. Add non-text output formats to pg_dumpall

  1. Documentation clarification request: pg_dumpall and Large Objects

    Radoulov, Dimitre <cichomitiko@gmail.com> — 2025-12-04T12:12:50Z

    Hello,

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.

In the source code (pg_dumpall.c), there is a comment indicating
that pg_dumpall forces all pg_dump output to plain text. Since Large
Objects are only included by pg_dump when using -b or non-text
archive formats (custom/tar), pg_dumpall cannot include LOBs 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."

This clarification would help prevent user confusion during
cluster-wide backup procedures.

Thank you.

Best regards,
Dimitre Radoulov

  2. Re: Documentation clarification request: pg_dumpall and Large Objects

    Laurenz Albe <laurenz.albe@cybertec.at> — 2025-12-04T15:50:55Z

    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.

Yours,
Laurenz Albe

  3. Re: Documentation clarification request: pg_dumpall and Large Objects

    Radoulov, Dimitre <cichomitiko@gmail.com> — 2025-12-04T17:12:53Z

    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

>

  4. Re: Documentation clarification request: pg_dumpall and Large Objects

    Laurenz Albe <laurenz.albe@cybertec.at> — 2025-12-04T18:11:44Z

    On Thu, 2025-12-04 at 18:12 +0100, Radoulov, Dimitre wrote:
> 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.
> > 
> > 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 again for your time and for considering the suggestion.

Attached is a patch for such a change.

I'll add it to the next commitfest.

Yours,
Laurenz Albe

  5. Re: Documentation clarification request: pg_dumpall and Large Objects

    Laurenz Albe <laurenz.albe@cybertec.at> — 2026-02-27T22:23:35Z

    On Thu, 2025-12-04 at 19:11 +0100, Laurenz Albe wrote:
> On Thu, 2025-12-04 at 18:12 +0100, Radoulov, Dimitre wrote:
> > 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.
> > > 
> > > 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.
> 
> Attached is a patch for such a change.

Commit 763aaa06f0 has changed the situation: with the addition of other formats
than the plain format, it no longer makes sense to say that pg_dumpall
is not useful for backup.  Still, we should clarify what is *not* included.

The attached patch does that and in passing improves the readability.

Yours,
Laurenz Albe

  6. Re: Documentation clarification request: pg_dumpall and Large Objects

    Radoulov, Dimitre <cichomitiko@gmail.com> — 2026-02-28T09:45:40Z

    Il Ven 27 Feb 2026, 23:23 Laurenz Albe <laurenz.albe@cybertec.at> ha
scritto:

> On Thu, 2025-12-04 at 19:11 +0100, Laurenz Albe wrote:
> > On Thu, 2025-12-04 at 18:12 +0100, Radoulov, Dimitre wrote:
> > > 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.
> > > >
> > > > 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.
> >
> > Attached is a patch for such a change.
>
> Commit 763aaa06f0 has changed the situation: with the addition of other
> formats
> than the plain format, it no longer makes sense to say that pg_dumpall
> is not useful for backup.  Still, we should clarify what is *not* included.
>
> The attached patch does that and in passing improves the readability.
>


Thank you for the update.

Best regards
Dimitre

>

  7. Re: Documentation clarification request: pg_dumpall and Large Objects

    Tom Lane <tgl@sss.pgh.pa.us> — 2026-03-29T17:55:11Z

    Laurenz Albe <laurenz.albe@cybertec.at> writes:
> Commit 763aaa06f0 has changed the situation: with the addition of other formats
> than the plain format, it no longer makes sense to say that pg_dumpall
> is not useful for backup.  Still, we should clarify what is *not* included.

> The attached patch does that and in passing improves the readability.

Pushed with trivial grammatical adjustments.  I also failed to resist
the temptation to improve the newly-added text nearby.

			regards, tom lane

  8. Re: Documentation clarification request: pg_dumpall and Large Objects

    Laurenz Albe <laurenz.albe@cybertec.at> — 2026-03-29T18:12:17Z

    On Sun, 2026-03-29 at 13:55 -0400, Tom Lane wrote:
> Laurenz Albe <laurenz.albe@cybertec.at> writes:
> > Commit 763aaa06f0 has changed the situation: with the addition of other formats
> > than the plain format, it no longer makes sense to say that pg_dumpall
> > is not useful for backup.  Still, we should clarify what is *not* included.
> 
> > The attached patch does that and in passing improves the readability.
> 
> Pushed with trivial grammatical adjustments.  I also failed to resist
> the temptation to improve the newly-added text nearby.

Thank you,
Laurenz Albe