Stephan Szabo <sszabo@megazone.bigpanda.com> writes:
> Yeah, mod is probably better and more general than case. It's still fairly
> ugly to require a non-trivial expression to get something that's
> consistent with the way that extract(week from date) works. ;)
> For anyone who is considering using this, to get an actual iso day of
> week, I think you'll need to add 1 at the end since that appears to use a
> 1-7 range. If you're just using it for sorting or the like, you can get
> away with not bothering.
Yeah. If we were to invent an extract(isodow) option, I'd be inclined
to make it return 1-7 Mon-Sun. So it'd actually produce the same value
as extract(dow), except on Sundays.
regards, tom lane