Question

Question 3. Let F be the following collection of functional dependenciesfor relation schema R = (A, B,C, D, E): D → A---BA→ C----C → E----E → DB. (i) Compute three

non-trivial new FDs in the closure F+ of F (i.e., FDs that are not already in F and also are not trivial). Describe briefly how you computed these new FDs (namely, how you applied Armstrong's axioms, step by step, to computed them). (ii) Provide at least one candidate key for R, and briefly explain how you obtained it (namely, explain briefly why it is indeed a candidate key).

Fig: 1

Fig: 2

Fig: 3

Fig: 4