SELECT
     C.CUST_CODE  AS CODE
    ,C.CUST_NAME AS NAME
    ,COUNT(O.ORDER_NO) AS CNT
    ,SUM(ORDER_AMNT)+SUM(CMP_TAX) AS TTL_AMT
    ,(SUM(ORDER_AMNT)+SUM(CMP_TAX))/COUNT(O.ORDER_NO)  AS AVG_AMT
FROM ORDERS O
LEFT JOIN CUSTOMER C
ON O.CUST_CODE = C.CUST_CODE
HAVING CNT >= 5
--GROUP BY O.CUST_CODE
ORDER BY CNT DESC , AVG_AMT DESC ,CODE ASC
LIMIT 5