2_
SELECT DEPARTMENT.name,
location.regional_group
FROM DEPARTMENT
JOIN LOCATION
ON department.location_id = location.location_id
JOIN EMPLOYEE E
ON E.department_id = DEPARTMENT.department_id
GROUP BY
DEPARTMENT.name,
location.regional_group
HAVING max(case when e.manager_id=e.employee_id then e.salary else 0 end)>max(case when e.manager_id<>e.employee_id then e.salary else 0 end)+1500