Re: abnormal forms

"paul c" <toledobythesea_at_oohay.ac> wrote in message news:QHa%f.6021$WI1.5342_at_pd7tw2no...

> First, I have a presumption that two relations can express the same
> value in different ways, ie., via different descriptions or expressions.
> For example, most people are familiar with the axiomatic attitude
> that different writings of attribute/column order don't change anything
> material.

> The first question is, is there anything axiomatic about an sva
> (single-valued attributes) relation when compared to an rva relation
> that has the same attributes?

> For example, (using ttm-style braces and for convenience omitting type
> names), is a SUPP{S#} relation logically the same value as a SUPP{{S#}}
> relation that is (somehow) constrained to have only one tuple? (not to
> be confused with one that somehow allows multiple tuples).

Maybe you should define an abnormal join first. :-) Received on Thu Apr 13 2006 - 10:19:28 CDT