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Question

Consider a relation scheme R = (A, B, C, D, E, H) on which the following functional dependencies hold: {A–>B, BC–>D, E–>C, D–>A}. What are the candidate keys of R?

a.

AE, BE

b.

AE, BE, DE

c.

AEH, BEH, BCH

d.

AEH, BEH, DEH

Answer: (d).AEH, BEH, DEH

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Q. Consider a relation scheme R = (A, B, C, D, E, H) on which the following functional dependencies hold: {A–>B, BC–>D, E–>C, D–>A}. What are the candidate keys of R?

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