Re: So what's null then if it's not nothing?

Jon Heggland wrote:
[...]
>
> I prefer to avoid NULLs altogether. But as I'm sure you know, even SQL
> considers NULLs equal in many circumstances.

Well, I do not know that. Could you give an example other than "order by" (which by the way does not involve comparison between null attributes at least at the logical level) ?

>
> > If not so, why do we
> > need to modify our query at all ? The standard SQL does not evaluate
> > null=null to true, so why bother writing the query "so as to disregard
> > people with NULL country" ?
>
> To avoid 3VL.

If you said, "to avoid 3vl SQL implementation inconsistencies", I'd agree ;)

> --
> Jon
Received on Sun Nov 27 2005 - 18:54:01 CET