刚写了一个感觉灰常复杂的 sql，感觉可读性不强啊，有什么好招

UPDATE order_items AS U1
          INNER JOIN
      (SELECT
          X.provider_id,
              X.product_id,
              X.order_id,
              X.model_id,
              Y.qty,
              (SELECT
                      M.price * N.discount
                  FROM
                      quotation AS M
                  LEFT JOIN quotation_discount N ON M.provider_id = N.provider_id
                      AND M.product_id = N.product_id
                  WHERE
                      M.model_id = X.model_id
                          AND M.provider_id = X.provider_id
                          AND Y.qty BETWEEN N.min_quantity AND N.max_quantity) AS price
      FROM
          (SELECT
          A.model_id, A.order_id, B.provider_id, C.product_id
      FROM
          order_inquiry_items A
      LEFT JOIN order_inquiry B ON A.order_inquiry_id = B.id
      LEFT JOIN product_model C ON A.model_id = C.id
      WHERE
          A.order_id = 23 AND B.provider_id = 14
              AND C.product_id = 1) AS X
      LEFT JOIN order_items Y ON X.model_id = Y.model_id
          AND X.model_id = Y.model_id) AS U2 ON U1.order_id = U2.order_id
          AND U1.model_id = U2.model_id
  SET
      U1.price = U2.price