select b.manager_name , a.employee_name , c.dept_name
  from employee  a, manager  b  , department  c
 where a.manager_id  = b.manager_id 
  and  a.dept_id = c.dept_id

    select  lpad(' ',level*2,' ')||ename name, dname, level
    from emp a join dept b using (deptno)
    START WITH  mgr is null
    CONNECT BY PRIOR EMPNO = MGR
    union  all
    select  dname, dname,0 from dept
    order by dname , 3