> and extract(day) from that gives -2 not -3. You could argue that this
> definition of timestamp subtraction isn't too consistent with the
> timestamp-plus-interval operator, and you'd be right; but I doubt we'd
> consider changing it now.
We specifically added that feature to support production calendaring
applications; I worked on it with Karel. When someone calendars a event
to be "3 days later" they don't expect it to jump by an hour because it
crossed a DST boundary. So changing it would break a bunch of people's
apps, especially mine.
--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com