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Question

Consider a schema R(A, B, C, D) and functional dependencies A->B and C->D. Then the decomposition R1(A, B) and R2(C, D) is

a.

Dependency preserving but not lossless join

b.

Dependency preserving and lossless join

c.

Lossless Join but not dependency preserving

d.

Lossless Join

Answer: (a).Dependency preserving but not lossless join

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Q. Consider a schema R(A, B, C, D) and functional dependencies A->B and C->D. Then the decomposition R1(A, B) and R2(C, D) is

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