Re: DB size

On Tue, Apr 27, 2021 at 8:59 AM Laurenz Albe <laurenz.albe@cybertec.at> wrote:
>
> On Mon, 2021-04-26 at 16:45 -0400, Alvaro Herrera wrote:
> > I would guess that there are leftover files because of those crashes you
> > mentioned.  You can probably look for files in the database subdir in
> > the data directory that do not appear in the pg_class.relfilenode
> > listing for the database.
>
> Not all tables have their "relfilenode" set:
>
> SELECT relfilenode FROM pg_class WHERE relname = 'pg_class';
>  relfilenode
> ═════════════
>            0
> (1 row)

Yeah, you want to use pg_relation_filenode(oid) rather than looking
directly at relfilenode.

When compared to the filesystem, it's probably even easier to use
pg_relation_filepath(oid).

--
 Magnus Hagander
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