Re: Simple Query
From: Bhalchandra Ghatate <bhala_at_cs.utexas.edu>
Date: 6 Feb 1995 10:24:39 -0600
Message-ID: <3h5ig7$mbo_at_peaches.cs.utexas.edu>
> name not in ('1', '2', '') expands to
> not (name='1' or name='2' or name=null) which reduces to
> not (TRUE or FALSE or NULL) which reduces to
> not (NULL) which reduces to
> NULL which isn't TRUE.
Date: 6 Feb 1995 10:24:39 -0600
Message-ID: <3h5ig7$mbo_at_peaches.cs.utexas.edu>
>
> name not in ('1', '2', '') expands to
> not (name='1' or name='2' or name=null) which reduces to
> not (TRUE or FALSE or NULL) which reduces to
> not (NULL) which reduces to
> NULL which isn't TRUE.
I think that is what Oracle might say.
So a '' is treated as a null not an empty string which is what it is.
with the same logic 0 should be treated as a NULL too.
I agree with your logic above but not Oracle's choicing of what defines a NULL. Received on Mon Feb 06 1995 - 17:24:39 CET