Re: IS (NULL = 1) equal to NOT(NULL = 1)?

John Dennis <jtdennis_at_atl.mindspring.com> wrote in article <4vflmd$1fti_at_mule2.mindspring.com>...
>
> Of course not right? Oracle says it is!

< --SNIP-- Because Internet Explorer told me I was quoting too much>

> Now I've been doing this for a while. I know that 1 is not equal to
> NULL. I thought this meant (1 = NULL) = FALSE which might be true.
> However if it is true then certainly NOT(1 = NULL) would then be TRUE.
> NOT of *any* expression is the opposite boolean value. But not here.
>
> Anyway, if anyone could point out my error here please do so. I
> wouldn't even mind a little "... any rookie that knows anything know
> should know that null, etc..." stuff. Hmmm, well maybe not.
>
> Virtually,
>
> John Dennis
>

1 is not equal to NULL, but it's also NOT not equal to NULL. That's the problem.
You can't perform equality operations against NULL because NULL by definition
is not equal to anything. NULL is undefined. The only explanation that I can give for the NOT(1 = NULL) result is that Oracle
is trying to tell you that you can't compare 1 to NULL in any way.

Shawn Received on Fri Aug 23 1996 - 00:00:00 CEST