Re: MV Keys

From: Marshall Spight <marshall.spight_at_gmail.com>
Date: 9 Mar 2006 19:18:19 -0800
Message-ID: <1141960699.034728.180770@p10g2000cwp.googlegroups.com>

dawn wrote:
> Marshall Spight wrote:
>
> Maybe the way to say it is that anything that can be modeled as a tuple
> can be modeled as a set with one tuple element. So you are right that
> you don't need a tuple type separate from a relation type IMO. If you
> have relation operators, you can take any tuple and treat it as a set
> of one tuple. --dawn

Or, maybe another approach would be for me to say that tuples do exist, but only in the context of relations, and even though they exist, there are no operators to extract them from the relations they are in.

Like with an array: an array is a collection of updatable cells, but there's no cell primitive. You can't have a cell in isolation by itself, but if you really wanted one, you could make a one-long array that had a single cell in it, and use that.

Marshall Received on Thu Mar 09 2006 - 21:18:19 CST