Re: Relational Algebra and Aggregate Functions

On Tuesday 28 July 2009 04:38:03 Jeff Davis wrote:
> On Mon, 2009-07-27 at 21:05 -0400, Robert James wrote:
> > 1) Introduction to Database Systems
> > http://www.amazon.com/Introduction-Database-Systems-Kannan-Swamynathan/dp
> >/B001BVYKY4/ref=sr_1_5?ie=UTF8&s=books&qid=1248742811&sr=1-5
> >
> > and
> > 2) Database in Depth: Relational Theory for Practitioners
> > http://www.amazon.com/Database-Depth-Relational-Theory-Practitioners/dp/0
> >596100124/ref=sr_1_7?ie=UTF8&s=books&qid=1248742811&sr=1-7
>
> I recommend #2. It's shorter and easier to read than "An Introduction to
> Database Systems", and I think it will answer your question about
> relational theory and aggregates (see "SUMMARIZE").

Is it weird that "Database in Depth" is shorter and easier than "Introduction
to Database Systems"?  And they're by the same author, too.