Re: Is a function a relation?
Date: Tue, 30 Jun 2009 01:49:15 -0700 (PDT)
On 30 juin, 03:51, David BL <davi..._at_iinet.net.au> wrote:
> On Jun 29, 11:01 pm, Cimode <cim..._at_hotmail.com> wrote:
> > <<
> > Given a relation type (i.e. schema), there are a number (possibly
> > infinite) of relation values that conform to that type. The type and
> > the values of that type are all abstract and carry almost no
> > information. >>
> > The cardinality of un-ary relation subtype can *not* exceed the
> > cardinality of the relation supertype. That is a constraint imposed
> > by how a relation is defined.
> Sure. Why did you say that?
Just a word of caution over the term *infinite*. Received on Tue Jun 30 2009 - 10:49:15 CEST