The E-R Model

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The E-R Model

  1. The entity-relationship model is based on a perception of the world as consisting of a collection of basic objects (entities) and relationships among these objects.

    We'll see later how well this model works to describe real world situations.

  2. The overall logical structure of a database can be expressed graphically by an E-R diagram: See figure 1.2 for an example.

    Figure 1.2: A sample E-R diagram.

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Last Update: Sun Sep 10 16:58:49 PDT 1995