Difficulty: Easy
Correct Answer: Correct
Explanation:
Introduction / Context:
Two complementary modeling operations exist: generalization and specialization. Specialization starts with a general entity and creates subtypes; generalization starts with several specific entities and abstracts a common supertype. Distinguishing these is central to flexible data modeling.
Given Data / Assumptions:
Concept / Approach:
Generalization identifies shared identity and attributes across distinct but related entities and defines a new supertype to capture those shared properties. For instance, Patient and Physician may be generalized to Person to hold name, birth_date, and address. The original entities become subtypes that add unique attributes (license_number for Physician, insurance_id for Patient).
Step-by-Step Solution:
Verification / Alternative check:
After generalization, queries for common attributes occur against the supertype; subtype-specific queries still work but benefit from shared identity and reduced redundancy.
Why Other Options Are Wrong:
Common Pitfalls:
Overgeneralizing unrelated entities, which can produce artificial supertypes and complicate constraints. Always validate generalization with real business semantics.
Final Answer:
Correct
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