Re: A question for Mr. Celko

"John Jacob" <jingleheimerschmitt_at_hotmail.com> wrote in message news:72f08f6c.0407190956.7531f88a_at_posting.google.com...
> > Not all interpretations of 1NF say that they are disallowed. The one that
> > makes the most sense to me says that the value should be atomic from the
> > database's perspective. In that case you can have any value in an attrbute
> > but you are not allowed to "break it open" which means you cannot have the
> > nest and unnest operations from the nested relational algebra.
>
> I'm sorry, I don't know what you mean by "break it open". If the value
> is contained within an attribute, how is it any different to have a
> relation value versus a date/time value? Clearly there are operators
> that allow me to access the components of the value in each case, so
> why does it matter whether the value is a relation, list, struct,
> etc.,.?

Yes, that's exactly the question. You said it better than I did.

Marshall Received on Mon Jul 19 2004 - 13:30:04 CDT