Second Normal Form

In this lesson, we will discuss how to decompose a table into second normal form and see some examples.

We'll cover the following...

Second normal form (2NF)

To be in second normal form, a relation must be in first normal form (1NF) and it must not contain any partial dependencies. So a relation is in 2NF as long as it has no partial dependencies, i.e., no non-prime attributes (attributes which are not part of any candidate key) is dependent on any proper subset of a composite primary key of the table.

Example

STUDENT Relation

Stud_Id Course_Id Course_Fee
1 C1 1000
...