Re: defaults on updates

Martin Marques <martin(at)bugs(dot)unl(dot)edu(dot)ar> writes:
> Basically, I have 5 fields, one being a PK (SERIAL), 3 with information, and
> the last one a timestamp field that will show the last time the register was
> modified (tmodif which has a DEFAULT CURRENT_TIMESTAMP).

> Now, eveytime someone modifys any, or all of the 3 information fields,
> I want the tmodif field of that register to be set to now().

This is trivial to do with a trigger --- you just need something like

NEW.lastmod := now();
RETURN NEW;

There's a complete example at the bottom of this page:
http://developer.postgresql.org/docs/postgres/plpgsql-trigger.html

regards, tom lane