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

vc wrote:
> Torkel Franzen wrote:
> > "JOG" <jog_at_cs.nott.ac.uk> writes:
> >
> > > So Godel's
> > > stated that any recursive axiomatic system cannot be consistent and
> > > complete.
> >
> > Not at all. There are lots of consistent and complete recursively
> > axiomatized systems.
>
> Right, Presburger arithmetic is one example.
>
> >As usual, Godel's theorem is supremely
> > irrelevant.
>
> And, yes, G.T. is irrelevant.

Amen - that's why the first post made no mention to it, the second only as an oblique reference to explain an hofstadter quote about djinns, and a later post stating "Now this has _nothing_ at all to do with the discussion except as a sweeping analogy for boundaries between different levels of interpretation". I guess it is standard web forum fare for people to get hung up on these things, but it was all tangential to the point at hand:

If you have an integer column, say, that allows nulls, its domain is: {I, Null} (where I represents the integers). While the integers were originally well ordered over the operators that SQL queries, now we have a Null element that is _incomparable_ to anything else in the set, yielding a poset. This to my mind makes a theorem like 3<Null invalid as the two items incomparable. My question is - is this not a stumbling block before you even reach the point where one can debate whether a 3VL be layered on top? All best, Jim. Received on Tue Dec 13 2005 - 11:59:51 CET