• Unit 4: The Entity-Relationship Model

    Databases often hold a great amount of data. In order to build a database, we need to understand which entities should hold data and identify the connections that may exist between entities. In this unit, we will learn about the Entity-Relationship model, which will allow us to create a graphical view of the different elements of a database as well as the relationships between them. We will also learn the drawing conventions of the E-R model using a part-to-whole approach, beginning with those conventions used to represent a single entity, and concluding with conventions used to represent all relations in a database. An E-R model is a model of a database's requirements. If we view database development from the perspective of a software life-cycle model, E-R modeling corresponds to requirements analysis. In database terms, this is called conceptual modeling.

    Completing this unit should take you approximately 5 hours.

    • 4.1: Why Use an E-R Model?

    • 4.2: E-R Elements and Symbols

    • 4.3: The Enhanced E-R Model

    • Unit 4 Assessment