Re: Vacuum Question

"Pascal PEYRE" <peyre@cir.fr> writes:
> I have some big postgreSQL databases (4/5 GB at start) on this server.
> Every night I erase data and I import a lot of new data.

Exactly how do you erase the old data?  If you're zapping the entire
contents of tables, TRUNCATE might be a good answer.

> For optimize my database I operate a vacuum "all" every night.

Plain vacuum, or vacuum full?  If it's a plain vacuum, do you have the
free space map parameters (in postgresql.conf) set large enough to cover
your database?

> The problem is that the size of database is growing every day whereas
> the volume of data stay remains stable.

Exactly which tables are bloating?  Look at the relpages column of
pg_class (just after a vacuum, so that the values are up to date).
Look to see which entries grow from day to day...

            regards, tom lane