Relationships at the supertype level indicate that all subtypes will

Relationships at the supertype level indicate that

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Relationships at the supertype level indicate that all subtypes will participate in the relationship The instances of a subtype may participate in a relationship unique to that subtype. In this situation, the relationship is shown at the subtype level
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Figure 3-3 Supertype/subtype relationships in a hospital Relationships and Subtypes
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Agenda Supertype and Subtype Generalization and Specialization Constraints in Supertype/Subtype
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Generalization and Specialization Generalization: The process of defining a more general entity type from a set of more specialized entity types. BOTTOM - UP Specialization: The process of defining one or more subtypes of the supertype and forming supertype/subtype relationships. TOP - DOWN
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