Full Outer Join!

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FULL OUTER JOIN: 
(i) HR manager to data analyst:  Bring me the details of employees and their corresponding department details and the details of department who doesn’t have any employee.

SELECT * FROM EMPLOYEES E FULL OUTER JOIN DEPARTMENTS D ON E.DEPARTMENT_ID= D.DEPARTMENT_ID;

(ii) HR manager to data analyst: Bring me the details of job history with its corresponding job details and the details of job which doesn’t have job history.

 SELECT * FROM JOB_HISTORY JH FULL OUTER JOIN JOBS J ON JH.JOB_ID= J.JOB_ID; 

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