select d.dept_code, d.dept_name, o.order_no, c.cust_code, c.cust_name, o.order_amt
from tbl_orders as o
inner join tbl_dept as d
on o.dept_code = d.dept_code
left outer join tbl_cust as c
on o.cust_code = c.cust_code
order by o.dept_code asc, o.order_no asc;