August 23rd, 2012, 08:27 AM
Help in query
how would you select all customers who bought product 'a' but did not buy products 'b', Without using subselects. (make sure there are no customers bought product 'b' in the result.)
August 23rd, 2012, 08:43 AM
This sounds like homework.
Anyway, this is much too vague to give a concrete answer. In PostgreSQL, you might first select the customers with either product 'a' or 'b' and then use the "boolean_and" aggregate function to get the products with only 'a'.
August 23rd, 2012, 08:49 AM
your teacher is cruel, but there is a specific point
Originally Posted by Ranvir
we won't help you until you post your best effort for this assignment
by the way, is there a specific target database system, or is this a pure SQL question?