A relation is said to be in 2NF iff-
1)-It is 1NF
2)-There should not be any partial dependency.
Non-prime attribute should be fully functional dependent on key.
Part of key should not derive any non prime attribute when key is composite.
Prime attribute-The attribute which forms key is called prime attribute and attribute which do not forms key is called non-prime attribute.
(A,B,C,D) is a relation
is key then A,B,C is prime attribute and D is non-prime attribute.