CHAPTER 5

Developing a Data Model

In the previous chapters, you've seen how to determine the requirements of a database problem by considering the tasks users of the system need to carry out. Tasks were represented with use cases, and a simple data model was developed to represent the required data. In Chapter 4, you saw that a great deal can be learned about a problem by questioning some of the details of simple relationships, particularly the number of objects involved at each end of a relationship. In this chapter, you'll be introduced to a few problems that frequently occur in order to enlarge your armory for attacking tricky situations.