"Joshua D. Drake" <jd(at)commandprompt(dot)com> writes:
> As far as I know constraint exclusion doesn't work with date_part or
> extract().
Uh, you clipped the example in my message showing that it does,
at least in the particular case Kevin showed us.
There are some variants of date_part that aren't immutable, but timestamp
without tz isn't one of them.
Still, I agree that not depending on it would be better.
regards, tom lane