find the name of all departments that do actually have one or more employees assigned to them.
SELECT DISTINCT T2.department_name FROM employees AS T1 JOIN departments AS T2 ON T1.department_id  =  T2.department_id
SELECT DISTINCT T2.department_name FROM employees AS T1 JOIN departments AS T2 ON T1.department_id  =  T2.department_id
[{'DEPARTMENT_NAME': 'Executive'}, {'DEPARTMENT_NAME': 'IT'}, {'DEPARTMENT_NAME': 'Finance'}, {'DEPARTMENT_NAME': 'Purchasing'}, {'DEPARTMENT_NAME': 'Shipping'}, {'DEPARTMENT_NAME': 'Sales'}, {'DEPARTMENT_NAME': 'Administration'}, {'DEPARTMENT_NAME': 'Marketing'}, {'DEPARTMENT_NAME': 'Human Resources'}, {'DEPARTMENT_NAME': 'Public Relations'}, {'DEPARTMENT_NAME': 'Accounting'}]