Re: Is relational theory incomplete?

Yes, I am very familiar with the catalogs. Compared to other, more semantically rich data models, the catalogs represent a very sparse amount of metadata. There is for example little or no information on domains and how these domains inter-relate.

You apparently misread my original reply. I infact said that Gödel did not invalidate the relational model.

You identify intension with conceptual. That is a great leap and one that many analytical philosophers would not agree with. See Montague for example, who proposes that it concepts are extensions.

"Bob Badour" <bbadour_at_golden.net> wrote in message news:NvGdnbW12t0LQTKiRVn-jw_at_golden.net...
> Tom,
>
> The catalog in an rdbms is entirely meta-data and is a rich source of
> meta-data. Goedel's proof basically states that the conceptual level of
> discourse is necessary, which does not in any way invalidate any part of a
> logical data model.
>
> The combination of conceptual, logical and physical is complete. The
> relational model is the best known logical data model, and it specifically
> limits itself to the logical level of discourse for important reasons like
> separation of concerns.
>
> Regards,
> Bob
>
> "Tom Hester" <tom_at_metadata.com> wrote in message
> news:f488$3fafcb95$45033832$28183_at_msgid.meganewsservers.com...
> > Gödel's proof is of the incompleteness of arithmetic, not relational
> algebra
> > (or calculus, or...). Essentially, Gödel demonstrated that a theory of
> > arithmetic must contain at least one intensional statement of the form:
> > 'this sentence is false'.
> >
> > Arithmetic had always been assumed to be purely extensional. Codd's
> > relational theory was purely extensional. Remember all of the early
> caveats
> > on relational theory of the form 'first order function free'. Those
> caveats
> > were to insure that the theory was only extensional. To put it in other
> > words, it only dealt with sets of things in the real world. A
relational
> > model is a first order description of some subset of the real world.
> >
> > The cost of this purely extensional restriction is the almost total lack
> of
> > metadata information available in a relational system.
> >
> > "mountain man" <hobbit_at_southern_seaweed.com.op> wrote in message
> > news:xJzrb.4373$aT.2467_at_news-server.bigpond.net.au...
> > > Did Date ever make reference to Godel's
> > > incompleteness theorem? If so, how did
> > > he handle it?
> > >
> > > How does relational theory come to terms
> > > with Godel's incompleteness theorem?
> > >
> > >
> > >
> > >
> > >
> > > Farmer Brown
> > > Falls Creek
> > > OZ
> > > www.mountainman.com.au
> > >
> > >
> > >
> >
> >
>
>
Received on Mon Nov 10 2003 - 20:29:59 CET