Consider the schema R (A, B, C, D) and the functional dependencies A → B and C → D. If the decomposition is made as R1 (A, B) and R2 (C, D), then which of the following is TRUE ?

Preserves dependency and performs lossless join

Preserves dependency but cannot perform lossless join

Does not preserve dependency and cannot perform lossless join

Does not preserve dependency but performs lossless join

Consider the schema R (A, B, C, D) and the functional dependencies A

1.	Consider the schema R (A, B, C, D) and the functional dependencies A → B and C → D. If the decomposition is made as R1 (A, B) and R2 (C, D), then which of the following is TRUE ?
A.	Preserves dependency but cannot perform lossless join
B.	Preserves dependency and performs lossless join
C.	Does not preserve dependency and cannot perform lossless join
D.	Does not preserve dependency but performs lossless join
Answer» B. Preserves dependency and performs lossless join

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Consider the schema R (A, B, C, D) and the functional dependencies A → B and C → D. If the decomposition is made as R1 (A, B) and R2 (C, D), then which of the following is TRUE ?

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