Re: Proposal: 6NF
Date: Fri, 06 Oct 2006 14:15:12 GMT
Message-ID: <QxtVg.11$ms1.5_at_trndny05>
"David Portas" <REMOVE_BEFORE_REPLYING_dportas_at_acm.org> wrote in message
news:1160133403.293728.245040_at_m73g2000cwd.googlegroups.com...
> I have not dismissed nulls arbitrarily. There are good reasons to
> reject SQL's definition of a null. I'm still waiting for your
> definition. Apparently you don't have one for numerics so dare I ask if
> you have one for boolean? Do you have a null for a graphics image type
> or a date type or a cartesian co-ordinate? How does your null behave
> under the operators for those types? I think you have your work cut out
> here...
I don't know what Brian's going to say, but I'll give you my definition.
A null is a marker indicating the absence of a value, in a place where a
value might normally have been expected.
A null is not a value. A null has no type. And to borrow Roy's phrase,
"make of it what you will."