SELECT
    D.DEPT_CODE,
    D.DEPT_NAME,
    O.ORDER_NO,
    C.CUST_CODE,
    C.CUST_NAME,
    O.ORDER_AMT
FROM
    TBL_ORDERS O 
RIGHT OUTER JOIN
    TBL_DEPT D 
ON 
    O.DEPT_CODE = D.DEPT_CODE
LEFT OUTER JOIN
    TBL_CUST C
ON
    O.CUST_CODE = C.CUST_CODE
ORDER BY
    D.DEPT_CODE ASC,
    O.ORDER_NO ASC;