Re: Domain

"Marshall Spight" <mspight_at_dnai.com> wrote in message news:0TiIb.15996$xX.40748_at_attbi_s02...
> "Dawn M. Wolthuis" <dwolt_at_tincat-group.com> wrote in message
news:bsqv24$r4r$1_at_news.netins.net...
> >
> > I'd rather we start with Java
> > than SQL for defining types since what we need seems to be pretty much
there
> > already.
>
> Me, too. Java would be a huge step up from SQL with regards to
user-defined
> types.

And a huge step backward from SQL with regards to the level of expression. It's like saying you prefer fortran because it has more engineering code libraries.

The Java type system is primitive and a giant leap backward compared to the type system described in TTM.

> > Beware
> > of anyone who adds in words like "atomic" into definitions of "domain".
> > Unless we (as a profession) can find a useful definition of atomic, I'd
like
> > to leave such useless jargon out of database discussions altogether.
>
> Agreed. But I think atomic has a well-established meaning: "of or
> employing nuclear energy." No, wait, it's "indivisible." An atomic
> operation is one that cannot be broken down into smaller operations;
> it succeeds entirely or not at all. An atomic value is a value which
> cannot be broken up into subcomponents.

Thus all values in the relational model are atomic. The relational model does not divide domain values or attribute values into subcomponents. Received on Tue Dec 30 2003 - 19:53:21 CET