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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;