Question

Consider the following relation with set of functional dependencies

R(ABCDEF)

AB->CD, CD->EF, BC->DEF, D->B, CE->F

a) Identify the candidate keys in the above relation (with proper steps followed).

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

Answer 1

From the given functional dependencies

R(ABCDEF) AB->CD, CD->EF, BC->DEF, D->B, CE->F

Now,

$AB\rightarrow CD$

and $CD\rightarrow EF$

so, $AB\rightarrow ABCDEF$

hence, from the above, we can conclude that the primary key will be $AB$