I have a mysql db with 3 tables (this is supposed to be a db for a dvd rental store)
The exercise told us we had to identify primary/foreign keys and draw the relational model, create the tables, fill them in (random data) and answer some questions using sql queries.
I am stuck in the following question for the past 3 hours:
Show pairs of clients/producers where the client never rented a movie of that producer.
So if client A never rented a movie of producer B then the result should be
A B (A never rented a movie of Producer B)
Any help on this? this assignment had 4 tasks, managed to do the 4 but this one seems hard to do and mind breaking.