SELECT 
    ORDER_NO AS OD_NO,
    SLIP_COMMENT AS COMMENT,
    (LENGTH(SLIP_COMMENT) - LENGTH(REPLACE(SLIP_COMMENT, ',', '')))+1 AS CNT
FROM 
    ORDERS
ORDER BY
(LENGTH(SLIP_COMMENT) - LENGTH(REPLACE(SLIP_COMMENT, ',', '')))+1 DESC,
ORDER_NO DESC;