update sku 
set std_cost_price = sub.std_cost_price
, update_user_name = 'MODIFY'
, user_update_datetime = '2024-08-31 00:00:00'
from
 ( select sk1.goods_code, goods.std_cost_price, round(avg(sk1.st_cost_price)) as scp
   from sku sk1
   inner join goods
      on goods.goods_code = sk1.goods_code
   group by sk1.goods_code, goods.std_cost_price
 ) as sub
where sub.goods_code = sku.goods_code
  and sku.std_cost_price < sub.scp