WITH
    Ave AS (
        SELECT
            GOODS_CODE,
            ROUND(AVG(STD_COST_PRICE), 1) AS STD_COST_PRICE
        FROM
            SKU
        GROUP BY
            GOODS_CODE
    )
UPDATE SKU
SET
    STD_COST_PRICE = G.STD_COST_PRICE,
    UPDATE_USER_NAME = 'MODIFY',
    USER_UPDATE_DATETIME = '2024-08-31 00:00:00'
FROM
    SKU AS S
    INNER JOIN GOODS AS G ON G.GOODS_CODE = S.GOODS_CODE
    INNER JOIN Ave ON S.GOODS_CODE = Ave.GOODS_CODE
WHERE
    SKU.STD_COST_PRICE < Ave.STD_COST_PRICE