Re: MV Keys

From: Marshall Spight <marshall.spight_at_gmail.com>
Date: 6 Mar 2006 07:36:23 -0800
Message-ID: <1141659383.465669.99320@u72g2000cwu.googlegroups.com>

Jon Heggland wrote:

> I agree. Perhaps Marshall meant that if you have RVAs, you don't really
> need tuple attributes, because you can "simulate" them using a RVA with
> cardinality one (just like you can "simulate" a list using a
> relation)---not that a tuple is a special kind of relation?

But isn't a tuple a subtype of a relation? What definition of subtype would you care to use? Consisder the defintion of a relation: doesn't a tuple qualify?

> The operators
> of the respective type kinds are also rather different, of course.

Can you be more specific? What different operators are there?

Marshall Received on Mon Mar 06 2006 - 09:36:23 CST