Normal Forms

First Normal Form (1NF)

A relation is in 1NF if every attribute is a single-valued attribute or it does not contain any multi-valued or composite attribute, i.e., every attribute is an atomic attribute. If there is a composite or multi-valued attribute, it violates the 1NF. To solve this, we can create a new row for each of the values of the multi-valued attribute to convert the table into the 1NF.

Let’s take an example of a relational table EmployeeDetail that contains the details of the employees of the company.

To convert this table into 1NF, we make new rows with each Employee Phone Number as a new row as shown below: