Re: Need help with a college SQL exam question...

>>>>> "Josh" == Josh Berkus <josh@agliodbs.com> writes:
   Josh> It's  doable.  Just think "nested subselects"  and heavy use   Josh> of  the HAVING  clause.  They're also
screwingwith  you by   Josh>  providing an irrelevant  table (shop)  and not  providing a   Josh> relevant table
(makers). If I was the professor, I'd give   Josh> the question writer a D+ for database design ...
 

I would treat the table car_model as providing a complete list of
makes as well, i.e., "select distinct make from car_model" provides a
list of all car makes (from which the customer can borrow).

I'd agree that the database *should* have a makers table to constrain
the values of that column.  A real-life database without it is prone
to *lots* of data entry errors (let's see, should I put in GM, Chevy
or Chevrolet?).

roland
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