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Question

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

a.

dependency preserving and lossless join

b.

lossless join but not dependency preserving

c.

dependency preserving but not lossless join

d.

not dependency preserving and not lossless join

Posted under Normalization DBMS

Answer: (d).not dependency preserving and 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 of R into R1 (A, B) and R2(C, D) is

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