find out max salary between dept = 20 and 40 code example

Example: get max salary from each department sql

--Find out the name of top earner in each departments
--Output has Name, Department name and max salary of the department

SELECT E.FIRST_NAME , D.DEPARTMENT_NAME, E.SALARY
FROM EMPLOYEES E
JOIN DEPARTMENTS D ON E.DEPARTMENT_ID = D.DEPARTMENT_ID
WHERE SALARY IN(SELECT MAX(E.SALARY)
FROM EMPLOYEES E
JOIN DEPARTMENTS D ON E.DEPARTMENT_ID = D.DEPARTMENT_ID
GROUP BY DEPARTMENT_NAME);