Re: Experience and feedback on pg_restore --data-only

Laurenz Albe <laurenz.albe@cybertec.at>

From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Dimitrios Apostolou <jimis@gmx.net>, pgsql-general@lists.postgresql.org
Date: 2025-03-23T16:00:39Z
Lists: pgsql-general
On Thu, 2025-03-20 at 23:48 +0100, Dimitrios Apostolou wrote:
> Performance issues: (important as my db size is >5TB)
> 
> * WAL writes: I didn't manage to avoid writing to the WAL, despite having
>    setting wal_level=minimal. I even wrote my own function to ALTER all
>    tables to UNLOGGED, but failed with "could not change table T to
>    unlogged because it references logged table".  I'm out of ideas on this
>    one.

You'd have to create an load the table in the same transaction, that is,
you'd have to run pg_restore with --single-transaction.

> Any feedback for improving my process? Should I put these ideas somewhere
> as ideas for improvement on pg_restore?

You put your ideas in the right place.

Yours,
Laurenz Albe