Oracle FAQ | Your Portal to the Oracle Knowledge Grid |
Home -> Community -> Usenet -> comp.databases.theory -> Re: Do Data Models Need to built on a Mathematical Concept?
"Neo" <neo55592_at_hotmail.com> wrote in message news:4b45d3ad.0305061130.4b5719b4_at_posting.google.com...
> > > Ok, let me try to understand:
> > > "A *binary relation* from A to B is a subset of A x B."
> > > Since (NULL) is a subset of AxB, it is a binary relation!!!
> > > Since ((b,j)) is a subset of AxB, it is a binary relation.
> > > Since ((b,j), (b,k)) is a subset of AxB, it is a binary relation.
> > > Since ((b,j), (b,k), (b,l)) is a subset of AxB, it is a binary
> > > relation. and so on....
> >
> > Exactly so.
>
> So you really believe NULL is a binary relation?
> So you really believe a set consisting of binary relations IS A binary relation?
It's not a question of belief; it's a question of how the word is defined.
I really, truly believe that how I described it above is how many mathematicians and many math books define it.
In all seriousness, you might want to look up the definition of the word "definition" in the dictionary.
Marshall Received on Wed May 07 2003 - 00:18:52 CDT