Q9,paper 3, J13. For a database relation R(a, b, c, d) where the domains of a, b, c, d include only the atomic values. The functional dependency a ->c, b->d .holds in the following relation

(A) In 1NF not in 2NF

(B) In 2NF not in 3NF

(C) In 3NF

(D) In 1NF

Answer A.

A relation schema R is in second normal form (2NF). If every non key attribute A in R is fully functionally dependent on the primary key.

In R(a,b,c,d)

b->d

a->c.

There is not a single key which derives all the non key values. Hence it is not in 2^nd normal form.