Data Modeling and UML

Abstract

Over the past two decades, the Entity-Relationship (ER) method has become the most popular and widely used method for conceptual database design. On the other hand, the Unified Modeling Language (UML) is widely used in the object-oriented analysis and design world. Despite the dominance of object-oriented techniques during the software development design and development phase, object-oriented databases are still not in widespread use. Software designers and developers often turn to the relational databases to make their application objects persistent. This adds one more task in the ‘to-do’ list of the designer: to map objects into entities. Considering the fundamental differences between the two methods, this task could be a non-trivial task. The purpose of this chapter is to describe a process that can be used to map a class diagram into an ER diagram, and to discuss the potential of using the UML notation to draw the ER diagrams. An example of an actual systems design is used throughout to illustrate the mapping process, the associated problems encountered and how they could be resolved.