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

>>>>> "Josh" == Josh Berkus <josh(at)agliodbs(dot)com> writes:

Josh> It's doable. Just think "nested subselects" and heavy use
Josh> of the HAVING clause. They're also screwing with 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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