Consider Student(stuid, dept, clsroll) with FD1: stuid → dept, FD2: dept → stuid, FD3: stuid → clsroll, FD4: clsroll → stuid, FD5: dept → clsroll. Which functional dependencies can be removed to obtain a canonical cover?
A. FD2 and FD3
B. FD1 and FD5
C. FD5
D. FD1
Choose the correct answer from the options given below:
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Correct answer: B. A, C only
Explanation
All three attributes determine one another. Removing FD5 (implied by dept → stuid → clsroll) works. Removing FD2 and FD3 leaves the cycle stuid → dept → clsroll → stuid, which still implies everything. Removing FD1 (or FD1 and FD5) loses stuid → dept.More Database Management Systems questions
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