USING clause in Oracle

The USING clause specifies which columns to test for equality when two tables are joined.
it can be used insted of an ON clause in the Join operations.

Syntax:-

USING (simple-column-name)[,Simple-column-Name)*)



This example joins the department_id column in the employees and departments tables.



SELECT employees.employee_id, employees.last_name,
       departments.location_id, department_id
FROM   employees JOIN departments
USING (department_id) ;