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