On Fri, Mar 09, 2007 at 20:13:11 -0300, Jorge Godoy <jgodoy@xxxxxxxxx> wrote: > Bruno Wolff III <bruno@xxxxxxxx> writes: > > > No, it has to be inside the function so that the modular arithmetic is > > applied to it. > > Then there's the error I've shown from your command. Can you give me a > working one? This was with PostgreSQL 8.2.3. postgres=# select date_trunc('week', current_date + 1); date_trunc ------------------------ 2007-03-05 00:00:00-06 (1 row) It turns out DOW isn't available for date_trunc. You can probably use extract to get what you want. You probably should check that it works at DST transitions, since the date value is cast to a timestamp and if DST transitions happen at 0000 in your time zone, you might get an unexpected answer. postgres=# select extract(dow from current_date + 1); date_part ----------- 6 (1 row)