Question : If a decomposition results in spurious tuples after join, it is:
Solution :
Correct Answer : Lossy decomposition
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Question : Which of the following combinations represents the types of decomposition?
Solution :
Correct Answer : Lossy and Lossless
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Question : A decomposition is dependency preserving if:
Solution :
Correct Answer : All functional dependencies can be enforced without joining relations
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Question : Which of the following is NOT a goal of relational decomposition?
Solution :
Correct Answer : Increase data duplication
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Question : Which condition ensures that a decomposition of a relation is lossless join?
Solution :
Correct Answer : Common attributes form a superkey in at least one relation
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Question : Which normal form specifically deals with eliminating multivalued dependencies?
Solution :
Correct Answer : 4NF
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Question : A relation has attributes Employee, Skill, Language, where skills and languages are independent but both depend on Employee. This situation represents:
Solution :
Correct Answer : Multivalued Dependency
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Question : Which of the following statements about multivalued dependency is FALSE?
Solution :
Correct Answer : It is a special case of functional dependency
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Question : In a relation R(A, B, C), if A →→ B, which of the following must also hold (assuming attributes are independent)?
Solution :
Correct Answer : A →→ C
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Question : Which of the following best defines a multivalued dependency (MVD)?
Solution :
Correct Answer : One attribute determines multiple independent values of another attribute
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Question : Which of the following indicates a lossy join?
Solution :
Correct Answer : Some tuples are lost or spurious tuples are generated
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Question : Which normal form is primarily based on Join Dependency?
Solution :
Correct Answer : 5NF
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Question : Join dependency is a generalization of which concept?
Solution :
Correct Answer : Multivalued Dependency
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Question : A join dependency is considered trivial when:
Solution :
Correct Answer : The join of decomposed relations gives the original relation without adding value
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Question : Which of the following best defines a Join Dependency (JD)?
Solution :
Correct Answer : A condition where a relation can be reconstructed by joining its projections
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Question : Which scenario violates inclusion dependency?
Solution :
Correct Answer : Some foreign key values are missing in the parent table
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Question : Given relations R(A, B) and S(C, D), which condition shows inclusion dependency?
Solution :
Correct Answer : R[A] ⊆ S[C]
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Question : Inclusion dependency is most closely related to:
Solution :
Correct Answer : Foreign key constraint
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Question : Which of the following best represents inclusion dependency?
Solution :
Correct Answer : R[X] ⊆ S[Y]
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Question : In DBMS, an inclusion dependency (IND) states that:
Solution :
Correct Answer : Values of one relation must be a subset of another relation
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Question : Which of the following statements about canonical cover is TRUE?
Solution :
Correct Answer : It may have multiple equivalent forms
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Question : An attribute in a functional dependency is called extraneous if:
Solution :
Correct Answer : It can be removed without affecting closure
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Question : Which step is NOT part of computing a canonical cover?
Solution :
Correct Answer : Adding transitive dependencies explicitly
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Question : Given F = { A → BC, B → C, A → B }, what is the canonical cover?
Solution :
Correct Answer : { A → B, B → C }
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Question : Which of the following best defines a canonical cover of a set of functional dependencies?
Solution :
Correct Answer : A minimal set of dependencies equivalent to the original set
Description -