Re: Changing locale of an existing database

On 6/17/25 09:20, Marcin Gozdalik wrote:
> Hi
>
> I am using PostgreSQL 17 and would like to take advantage of performance
> and stability across OS updates of builtin C.UTF-8 locale.
> I have a cluster with a DB created with en_US.UTF-8 libc locale. I would
> like to migrate the DB to C.UTF-8. Ideally there'd be an "ALTER DATABASE
> ... SET LOCALE ..." command that would take care of it but it seems it
> doesn't exist. I was thinking that I could change the collation of all
> TEXT/CHAR/VARCHAR columns in all the tables to pg_c_utf8, REINDEX all
> those columns and change the default locale in the pg_database table.
>
> Is it a sensible plan? Am I missing some steps? I can't find any
> reference to anybody doing that before or discouraging it.

How big a database are we talking about?

To me it would seem easier to create a new database with new locale and
do either a pg_dump/pg_restore or logical replication to the new
instance. Of course this may depend on the answer to the question above.

>
> Thanks,
> Marcin
>
> --
> Marcin Gozdalik

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com