Re: extract (dow/week from date)

On Sat, 20 Aug 2005, Tom Lane wrote:

> Clodoaldo Pinto <clodoaldo.pinto@gmail.com> writes:
> > I'm ordering by date just to show that sunday, the 0th day of the
> > week, is the last day of a given week, which is not what I need.
>
> extract(week) follows the ISO definition of week, which is pretty
> strange anyway, but in particular it says that weeks start on Monday.
> extract(dow) follows a different convention.  There's not a lot we
> can do about this --- we're certainly not going to change extract(week),
> and I can't see changing extract(dow) either.

Instead of change the existing ones, couldn't we add a new extract format
for "iso day of week" that returns 1-7 for monday-sunday that would be
consistent with the week definition?