Howard Stearns writes:

 > What I'm trying to do -- and of course, this isn't a Squeak question at 
 > all, but I hope it is a Squeak community question -- is try to learn 
 > what domain a perfectly running RDBMS is a good fit for by design, 
 > compared with a perfectly running alternative (even a hypothetical one).
I'd say if you're placing the database schema at the center of your
large system or you're using the query facilities. Relational algebra
is often just powerful enough to model commercially interesting
systems. It's lack of expressive power makes it a very powerful system
to manipulate either during design or by a query optimizer.

The great strength of RDBMSes is they are a mathematically decidable
and complete system. If you can translate a problem into relational
algebra you can always find a solution however such a system is not
powerful enough to model arithmetic on natural numbers.

Bryce