Figure 4-33 (page 196) shows an EER diagram for a simplified credit card environment. There are two types of card accounts: debit cards and credit cards. Credit card accounts accumulate charges with merchants. Each charge is identified by the date and time of the charge as well as the primary keys of merchant and credit card.
a. Develop a relational schema.
b. Show the functional dependencies.
c. Develop a set of 3NF relations using an enterprise key.