When two or more tables have been joined using the equal to operator then this category is called an Equi join. Just we need to concentrate on the condition that is equal to (=) between the columns in the table.
Employee Table
| emp_id | emp_name | salary | dept_id | manager_id |
|---|---|---|---|---|
| E1 | Rahul | 15000 | D1 | M1 |
| E2 | Manoj | 15000 | D1 | M1 |
| E3 | James | 55000 | D2 | M2 |
| E4 | Michael | 25000 | D2 | M2 |
| E5 | Ali | 20000 | D10 | M3 |
| E6 | Robin | 35000 | D10 | M3 |
Department Table
| dept_id | dept_name |
|---|---|
| D1 | IT |
| D2 | HR |
| D3 | Finance |
| D4 | Admin |
Example
The following SQL selects employees’ names and departments’ names from the above-given tables where the department Id is the same.
SELECT e.emp_name,d.dept_name
FROM Employee e, Department d
WHERE e.dept_id=d.dept_id
Output
| emp_name | dept_name |
|---|---|
| Rahul | IT |
| Manoj | IT |
| James | HR |
| Michael | HR |
Code Runner
Copy the below query in the code runner to see the result
SELECT e.emp_name,d.dept_name
FROM Employee e, Department d
WHERE e.dept_id=d.dept_id