WITH culc_avg AS (
    SELECT
        GOODS_CODE,
        (ROUND(AVG(STD_COST_PRICE)) * 10) / 10.0 AS AVG
    FROM SKU
    GROUP BY GOODS_CODE
),
unite AS (
    SELECT 
        g.GOODS_CODE AS GOODS_CODE,
        s.SKU_CODE AS SKU_CODE,
        g.STD_COST_PRICE AS COST
    FROM GOODS AS g
    INNER JOIN SKU AS s
    USING(GOODS_CODE)
)
UPDATE SKU
SET STD_COST_PRICE = (
    SELECT 
        COST
    FROM unite
    WHERE unite.SKU_CODE = SKU.SKU_CODE
),
UPDATE_USER_NAME = 'MODIFY',
USER_UPDATE_DATETIME = '2024-08-31 00:00:00'
WHERE STD_COST_PRICE < (
    SELECT AVG 
    FROM culc_avg AS c 
    WHERE c.GOODS_CODE = SKU.GOODS_CODE
)