Database Design Using Entity-Relationship Diagrams, 3rd Edition

5 Beyond the First Entity Diagram

DOI: 10.1201/9781003314455-5

5.1 INTRODUCTION

Now that we have devised a process for drawing, interpreting, and refining one primary entity, we need to move to more complex databases. To progress from here, we continue with our primary entity and look for other information associated with (related to) that entity.

The first technique employed in this chapter is methodical: We test our primary entity to see whether our attributes ought to be entities themselves. We then look for other pieces of information in our description, add them to:

1. An existing entity and examine the existing entity-relationship (ER) diagram
2. Create a new entity directly

After creating the new entities, we look to see what relationships ...