Question

. Consider the following relation with set of functional dependencies

R(ABCDEF)

ABC->D, ABD->E, CD->F, CDF->B, BF->D

a) Identify the candidate key(s) in the relation (with proper steps followed).

b) Identify which normal form this relation is in and reason for the answer.

Answer 1

We notice that on the right hand side of each relation, A and C aren't present. Therefore the candidate key comprises of A and C. We find the closure of AC and check the different combinations of AC.

Hence ABC, ABF are candidate keys