Re: By The Dawn's Normal Light

"erk" <eric.kaun_at_pnc.com> wrote in message news:1099342265.915878.79930_at_z14g2000cwz.googlegroups.com...

> I don't agree. The "original definition" depended on the definition of
> the term "atomic", didn't it? I'd say it was internally inconsistent;

I'd say that the terms "internally inconsistent" and "meaningless" are not interchangeable.

> though I don't have the papers here, if I recall Codd mentioned
> user-defined types, and their being black boxes (not his term) to the
> DBMS. That rules out the DBMS caring whether it's a list or not; all
> that matters is that the DBMS not have inherent knowledge of a
> "container" other than the relation (actually relvar).

All I've read is the reprint in 1995 of the original 1970 paper.

I've done very limited reading of Date. Such reading as I have done characterizes the Codd definition of 1NF as "unfortunate", not as "meaningless". It seems to me that Date is doing his best to advance and improve the state of the art without either failing to accord Codd the respect his work deserves or being bound by whatever limitations Codd's work may have had. I can't say the same for all the camp followers.

It seems to me that we need to settle (or at least agree to disagree) about whether Codd's work was "meaningful" or "meaningless" before we can even meaningfully discuss whether or not it was "internally inconsistent". Even if it turns out to be "internally consistent", it might still not be the most "useful" data model, of all the data models that are meaningful and internally consistent. It's that last point that I htink Date has addressed. Received on Tue Nov 02 2004 - 15:18:09 CET