In a schema R(A, B, C, D, E, F, G, H), each field of R contains only atomic values. F = {CH → G, A → BC, B → CFH, E → A, F → EG} is a set of functional dependencies, and F⁺ is exactly the set of FDs that hold on R. The relation R is:
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Correct answer: A. In 1NF, but not in 2NF
Explanation
D never appears on a right side, so every key contains D. A⁺ = {A, B, C, F, H, E, G}, so AD is a key (as are BD, ED and FD). The prime attributes are A, B, D, E, F, and C, G, H are non-prime. A → BC makes the non-prime C depend on part of the key AD, which is a partial dependency. So R is in 1NF but not 2NF.More Database Management Systems questions
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