UPDATE SKU
SET
STD_COST_PRICE = (SELECT STD_COST_PRICE FROM GOODS WHERE SKU.GOODS_CODE = GOODS.GOODS_CODE)
WHERE
SKU_CODE IN
(
SELECT
SKU_CODE
FROM
SKU S
WHERE
S.STD_COST_PRICE <
(
SELECT
ROUND(AVG(STD_COST_PRICE))
FROM
SKU S2
GROUP BY GOODS_CODE
)
)