Schema Translation - Information Systems Reengineering, Integration and Normalization - page 108

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Step 7—Map aggregation to composite class.
The entities and their relationship in the EER model can be aggregated to form
an entity. In an object-oriented model, this permits the combination of classes that
are related into a higher level composite class. For example, the aggregation in
Fig. 3.39 can be mapped to the object-oriented schema where the composite class
Section is an aggregation of two component classes: class Instructor and class