Generalization or specialization hierarchy: The arrangement of higher-level supertypes entity and lower-level subtypes entity is called as generalization or specialization hierarchy. The specialization hierarchy is a “is-a” relationship model. It contains many levels of subtype or supertype relationships. Subtype is related to an entity supertype, where the supertype entity has common characteristics and the subtype entity has the unique characteristics of each entity subtype.

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Chapter 6, Problem 12PE

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Generalization or specialization hierarchy:

The arrangement of higher-level supertypes entity and lower-level subtypes entity is called as generalization or specialization hierarchy.

The specialization hierarchy is a “is-a” relationship model.

It contains many levels of subtype or supertype relationships.

Subtype is related to an entity supertype, where the supertype entity has common characteristics and the subtype entity has the unique characteristics of each entity subtype.

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