Re: Proposal: 6NF

Hugo Kornelis wrote:
> 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.
Thanks for giving your take on that, Hugo, since I was clearly getting nowhere. I tried to be clear, repeatedly, that I was not talking about an SQL NULL, but perhaps was not clear enough. I was starting to think perhaps he lived in a world where the only null was an SQL NULL, so he did not know any other use of that term and just ignored it when I said that I was not talking about an SQL 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.

I tried to clarify both NULL and function to avoid this, but without getting definitions in return, I was unable to debug the conversation satisfactorily. Thanks for providing clues. --dawn Received on Tue Oct 10 2006 - 00:46:00 CEST