Re: Proposal: 6NF

On Fri, 06 Oct 2006 23:29:29 GMT, paul c wrote:

>Hugo Kornelis wrote:
(snip)
>> Because relational databases supporting NULL *define* it as a marker
>> denoting the absence of a value. Dawn actually makes a good point about
>> context: in C for instance, NULL has a completely different meaning.
>> ...
>
>Since it has a different meaning in C, there is no point bringing C into
>play here.

Hi Paul,

The point I was trying to make is that NULL has different meaning in different context. Using C as example was a bad choice, since it obfuscated what I was trying to convey, rather than clarifying it.

The meaning of NULL in the context of SQL is also quite different from the meaning of NULL in Pick (and possibly other MV databases). That's what I wanted to write, and what I should have written in the first place. Much of the discussion between Cimode and Dawn appears (as I read it) to come from Cimode talking aboout SQL NULL and Dawn talking about Pick NULL - but they both think that the other is discussing the same NULL. This group is about databases in general, not just about relational databases and definitely not only about SQL. The title of this thread also doesn't limit discussion to SQL databases only. So it makes sense to specify exactly what definition of NULL you're discussing - I think that the Cimode-Dawn exchange would have been a lot shorter if everyone had done that.

Best, Hugo Received on Tue Oct 10 2006 - 00:33:44 CEST