Re: RA with MV attributes

paul c wrote:
> David wrote:
>
> > ...
> > Why can't we say that *by definition* the set of attributes of a
> > relation is part of its state not its type?
> > ...
>
> We can say anything we want "by definition", the question is where does
> saying it get us? What conclusions does it lead to and so forth.

Marshall doesn't seem prepared to accept this definition on it face, because he has assumed that the set of attributes of a relation is surely its type.

> I
> like your suggestions because they seem to have something behind them,
> but don't ask me what, exactly. I wish you would distinguish whether
> you are talking about physical implementations or user concepts.

I guess this relates to the following discussion

http://www.ai.mit.edu/docs/articles/good-news/subsection3.2.1.html

I tend to think that both implementation and interface should be reasonably simple, and it's bad to strongly favor one at the expense of the other. I often look at what the implementation is telling me in order to design a reasonable interface. There is nothing better than getting your cake and eating it too. Received on Wed Jan 17 2007 - 05:02:36 CET