SELECT DP.DEPT_CODE, DP.DEPT_NAME, OD.ORDER_NO, CS.CUST_CODE, CS.CUST_NAME, OD.ORDER_AMT 
FROM TBL_ORDERS AS OD
INNER JOIN TBL_DEPT AS DP ON DP.DEPT_CODE = OD.DEPT_CODE
LEFT OUTER JOIN TBL_CUST AS CS ON CS.CUST_CODE = OD.CUST_CODE 
ORDER BY OD.DEPT_CODE ASC, OD.ORDER_NO;