pg_dumpall apparently has a -globals option that's supposed to backup everything, but the help for pg_dumpall shows a -g, --globals-only dump only

You can dump the whole PostgreSQL cluster with pg_dumpall. That's all the databases and all the globals for a single cluster. From the command line on the server, I'd do something like this. (Mine's listening on port 5433, not on the default port.) You may or may not need the --clean option.

$ pg_dumpall -U postgres -h localhost -p 5433 --clean --file=dump.sql

This includes the globals--information about users and groups, tablespaces, and so on.

If I were going to backup a single database and move it to a scratch server, I'd dump the database with pg_dump, and dump the globals with either

pg_dumpall --globals-only, or
pg_dumpall --roles-only (if you only need roles)
like this.

$ pg_dump -U postgres -h localhost -p 5433 --clean --file=sandbox.sql sandbox
$ pg_dumpall -U postgres -h localhost -p 5433 --clean --globals-only --file=globals.sql

Outputs are just text files.

After you move these files to a different server, load the globals first, then the database dump.

  $ psql -U postgres -h localhost -p 5433 < globals>

I thought pg_dumpall would at least backup foreign keys, but even that seems to be an 'option'. According to: http://www.postgresql.org/docs/9.1/static/app-pg-dumpall.html even with pg_dumpall I need to use a -o option to backup foreign keys


No, that reference says "Use this option if your application references the OID columns in some way (e.g., in a foreign key constraint). Otherwise, this option should not be used." (Emphasis added.) I think it's unlikely that your application references the OID columns. You don't need to use this option to "backup foreign keys". (Read the dump file in your editor or file viewer.)


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You are correct that there is some confusion around the options for pg_dumpall. The pg_dumpall utility is used to dump the entire contents of a PostgreSQL database cluster, including all databases and global objects such as roles and tablespaces.

The -g or --globals-only option specifically dumps only the global objects, without the actual database contents. Here's a clarification of the options:

-g, --globals-only: This option tells pg_dumpall to dump only the global objects. This includes roles and tablespaces, but not the data within the individual databases.

There is no -globals option in pg_dumpall. The confusion might come from misunderstanding the documentation or the way options are presented. The correct usage to dump all global objects (roles, tablespaces) is indeed pg_dumpall -g or pg_dumpall --globals-only.

Here's how you can use these options:

To dump everything (all databases and global objects):

  pg_dumpall > all_databases.sqlTo dump only global objects:pg_dumpall -g > globals.sql

If you want to back up everything (all databases and global objects), you simply run pg_dumpall without any special options. The -g option is specifically for when you only need the global objects.

For further details, you can refer to the official PostgreSQL documentation for pg_dumpall here.