1NF
First of all, let's check if the above relation is in 1NF. Since all the values in the table(relation) are atomic, we can say that the above relation is already in 1NF.
2NF
To check if the relation is in 2NF, let's check if there is any partial dependency. Here, E_ID is the Primary Key. Thus the following dependencies occur:
E_ID → E_Name
E_ID → E_Post
E_ID → E_Sex
E_ID → E_Salary
E_ID →E_Add
There aren't any partial dependencies here. Thus we can say that the above relation is already in 2NF.
3NF
Let's check if there are any transitive dependency in the above relation. The E_Salary can be determined from E_Post. Thus, the following transitive dependency occur:
E_ID → E_Post
E_Post → E_Salary
Thus, let's break down the relation into R1 and R2.
R1
| E_ID | E_Name | E_Post | E_Sex | E_Add |
|---|---|---|---|---|
| 1 | Rahul | Sr. Engineer | M | Kathmandu |
| 2 | Sushila | Web Developer | F | Birgunj |
| 3 | Rahul | Web Developer | M | Balaju |
| 4 | Sasim | Jr. Engineer | M | Dhangadhi |
| 5 | John | Jr. Engineer | M | New York |
R2
| E_Post | E_Salary |
|---|---|
| Sr. Engineer | 100000 |
| Web Developer | 40000 |
| Jr. Engineer | 70000 |
The transitive dependency is removed and hence the tables R1 and R2 are in 3NF.