Question

Consider the following relation R (A, B, C, D, E, F, G) and set of functional dependencies.

$F=\{BCD\to A,BC\to E,A\to F,F\to G,C\to D,A\to G\}$

Which of the following is minimal cover of F?

Answer 1

(1) RHS contain single attribute

$A\to F...\left(1\right)$

$F\to G...\left(2\right)$

$A\to G...\left(3\right)$

Hence FD' (3) is redundant.

Now consider

$BCD\to A$

$(BC{)}^{\ast }=BCEDAFG$

It contain attribute D, D is redundant.

Minimal cover is $|BC\to A,BC\to E,A\to F,F\to G,C\to D|$

So option (c) is correct.