text: select department_id as d_e_dept_id, e.last_name
     from departments
     full outer join employees on (a=b)
     left outer join employees on (a=b)
     right outer join employees on (a=b)
     join employees on (a=b)
     inner join employees on (a=b)
     cross join employees
     natural join employees
  
  
  
  
  	
  