Re: Interesting article: In the Beginning: An RDBMS history

From: x <x_at_not-exists.org>
Date: Tue, 11 Apr 2006 08:28:31 +0300
Message-ID: <e1fep2$915$1_at_emma.aioe.org>


"David Cressey" <dcressey_at_verizon.net> wrote in message news:O4w_f.7994$rm3.226_at_trndny06...
>
> "x" <x_at_not-exists.org> wrote in message news:e1dek1$vem$1_at_emma.aioe.org...
> >
> > "David Cressey" <dcressey_at_verizon.net> wrote in message
> > news:ZYNZf.133$ee6.86_at_trndny01...
> > >
> > > "mAsterdam" <mAsterdam_at_vrijdag.org> wrote in message
> > > news:4437030e$0$11073$e4fe514c_at_news.xs4all.nl...

> > Well, the question was more like: a relation with attribute names in
Chris
> > Date style is more similar to a Codd's relation, to a relationship or
to
> > something in between ?

> Ok, this wasn't the original post, but it was a question as you asked it.
> Here it is, verbatim:

> > What is the difference between a "name" and a "position" from a
> > mathematically point of view ?

Here it is, verbatim:

"What do you think is the difference between the Codd pi (projection/permutation) operator and Chris Date rename coupled with projection operators ?"

I know the question in the post that appeared :-) as a reply to you was the one you said. Received on Tue Apr 11 2006 - 07:28:31 CEST

Original text of this message