Learning Self Join!

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SELF JOIN

 Usage:
HR manager to data analyst: Bring me the employee ids along with the name of manager managing that employee. Data analyst runs below query to fetch the required data.

 SELECT E.EMPLOYEE_ID, M.EMPLOYEE_ID AS MANAGER_ID, M.FIRST_NAME, M.LAST_NAME FROM EMPLOYEES E, EMPLOYEES M
WHERE E.MANAGER_ID= M.EMPLOYEE_ID;








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