Second Normal Form (2NF) Normalisation in DBMS

To minimize redundancy from a relation or group of relations we use normalization. Insertion, deletion, and update anomalies could result from relational redundancy. Therefore, it helps to reduce relational redundancy. 

We use second normal form to reduce the redundancies. Second Normal Form (2NF) is based on the concept of full functional dependency. A relation with a single-attribute primary key is automatically in at least 2NF. 

A relation that is not in 2NF may suffer from the update anomalies. To be in second normal form, a relation must be in first normal form and relation must not contain any partial dependency. 

A relation that is in First Normal Form and every non-primary-key attribute is fully functionally dependent on the primary key, then the relation is in Second Normal Form (2NF). 

2NF in Normalisation: https://www.geeksforgeeks.org/second-normal-form-2nf/