Consider a relation R(A, B, C, D) with FDs A->B and C->D then the…
Consider a relation R(A, B, C, D) with FDs A->B and C->D then the decomposition of R into R1(A,B) and R2(C, D) is
Answer: C. Dependency preserving but not lossless — (c) R1(A,B) and R2(C,D) No common attribute so not lossless but is dependency preserving because R1 covers A->B and R2 covers C->D.
- A.
Dependency preserving and lossless
- B.
Lossless but not dependency preserving
- C.
Dependency preserving but not lossless
- D.
Not dependency preserving and not lossless
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Correct answer: C
(c)
R1(A,B) and R2(C,D)
No common attribute so not lossless but is dependency preserving because R1 covers A->B and R2 covers C->D.
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