On Fri, 2007-11-30 at 21:42 +0800, Lincoln Yeoh wrote:
> --- post follows ---
> by Anonymous Coward on Wed Nov 28, '07 03:23 PM (#21509173)
>
> Speak for your database -- postgresql does.
>
> Postgresql's "table inheritance" is a flawed concept and has nothing to do
> with the *type system*. Relations contain tuples, and tuples contain
> attributes, which are a name plus a VALUE. Those values are chosen from TYPES
> (sets of possible values). Those types are the TYPE SYSTEM.
"Foundation for Future Database Systems: The Third Manifesto" by C.J.
Date and Hugh Darwen discusses this topic in Appendix E, and a related
topic in Appendix D.
They also propose, in detail with a lot of analysis, how they think that
type inheritance should work in the set of chapters on the Inheritance
Model, or "IM".
Regards,
Jeff Davis