> So how can I create a trigger to automatically update the hash fields
> on updates and inserts?
Something like the following works for me:
create or replace function public.my_trigger()
returns trigger as '
NEW.hashfield = hashfunction(NEW.data1,NEW.data2);
RETURN NEW;
END;
' language 'plpgsql';
--------
create trigger my_trig
before insert or update on my_tablename
for each row
execute procedure public.my_trigger();
The 'RETURN NEW' part is very important, without it your hash field won't
get updated at all.
--
Mike Nolan