What are the prime attributes of relation R(A,B,C,D) with following dependencies:
F={AB->C , C->D , D->A}
options are: i) A,B,C ii) A,B,D iii) A,B,C,D iv) B,C,D
According to me answer should be (iii) option but answer is option (ii) Can anyone explain?
The candidate keys for the given set of functional dependencies are AB, BC and BD. Since all the attributes of the relation R are come at least once in one of the candidate keys, all of them are prime attributes. The given relation R is thus automatically in 3NF.
Option (iii) is right. The given answer is wrong.
