Re: NULLs ;-)

--- Scott Ribe <scott_ribe@killerbytes.com> wrote:

> > (Can we talk about NULL next? :P)
>
> Seriously though, there is one thing I've been meaning to bring up. I
> understand why NULLs compare the way they do in queries, and that's fine.
> But there are times when I need to query what would be described in
> relational terms as "not known to be equal", and
>
>  where a <> b or (a is null and b is not null) or (a is not null and b is
> null)
>
> is rather clumsy and verbose (though precise), especially when it needs to
> be combined with other criteria.
>
> So, first, have I missed some way to express that more easily in PG? And if
> not, is there any reason not to request a new operator? (Perhaps "a nktbe
> b"? The C guy in me prefers "a != b" but that would be *FAR* too prone to
> confusion with <>.)

how about

SELECT *
FROM
        YOURTABLE
where
  ( a = b ) IN UNKNOWN;