Re: Three Kinds of Logical Trees

dawn wrote:
> Marshall Spight wrote:
> > dawn wrote:
> > >
> > > I missed the word "set" before the ? I use a 2VL where a null is like
> > > a null set.
> >
> > What is a 'null set'? Is that like the empty set?
> >
> yes
>
> http://www.swif.uniba.it/lei/foldop/foldoc.cgi?null+set
> http://en.wikipedia.org/wiki/Null_set

Wow. I hadn't heard that term before. Given how much confusion there is around the semantics of null in SQL, I think I'm going to steer clear of it, especially in this field. I can easily see it causing confusion where the more popular "empty set" term wouldn't.

Marshall Received on Wed Jul 27 2005 - 20:47:09 CEST