Mysql 按日期分组和排序的复杂总和（）

有两个表格：

* ORDER 
  - id
  - pay_type
* ORDER_PRICE
  - order_id
  - dt
  - price

SELECT o.order_id
     , SUM(op.price) price
     , op.dt
  FROM orders o 
  JOIN order_price op
    ON op.order_id = o.order_id
  JOIN 
     ( SELECT order_id, MAX(dt) max_dt FROM order_price WHERE dt < '2013-10-26' GROUP BY order_id ) x
    ON x.order_id = op.order_id 
   AND x.max_dt = op.dt
 GROUP
    BY order_id,dt
  WITH ROLLUP;

订单价格可以更改，例如：

order_id | price | dt  
       1 | 100.3 | 2013-10-25  
       1 | 105.7 | 2013-10-28  
       2 | 207.4 | 2013-09-13  
       4 | 98.0 | 2013-10-03

SELECT o.order_id
     , SUM(op.price) price
     , op.dt
  FROM orders o 
  JOIN order_price op
    ON op.order_id = o.order_id
  JOIN 
     ( SELECT order_id, MAX(dt) max_dt FROM order_price WHERE dt < '2013-10-26' GROUP BY order_id ) x
    ON x.order_id = op.order_id 
   AND x.max_dt = op.dt
 GROUP
    BY order_id,dt
  WITH ROLLUP;

我可以选择任何日期的价格历史记录，如：

 SELECT 
o.`id`,
    (SELECT op.`price` FROM `order_price` op 
     WHERE op.`order_id`=o.`id` AND op.`dt` <= '2013-10-26'
     ORDER BY op.`dt` DESC LIMIT 1) order_price
    FROM `order` o 

SELECT o.order_id
     , SUM(op.price) price
     , op.dt
  FROM orders o 
  JOIN order_price op
    ON op.order_id = o.order_id
  JOIN 
     ( SELECT order_id, MAX(dt) max_dt FROM order_price WHERE dt < '2013-10-26' GROUP BY order_id ) x
    ON x.order_id = op.order_id 
   AND x.max_dt = op.dt
 GROUP
    BY order_id,dt
  WITH ROLLUP;

但我需要第二列的和，不管顺序号是什么，在本例中只有一个数字-405.7

SELECT o.order_id
     , SUM(op.price) price
     , op.dt
  FROM orders o 
  JOIN order_price op
    ON op.order_id = o.order_id
  JOIN 
     ( SELECT order_id, MAX(dt) max_dt FROM order_price WHERE dt < '2013-10-26' GROUP BY order_id ) x
    ON x.order_id = op.order_id 
   AND x.max_dt = op.dt
 GROUP
    BY order_id,dt
  WITH ROLLUP;

---

有没有解决这种情况的办法？可能有数千个订单，所以我认为在mysql之外对记录求和是错误的。也许从一开始就错了，我需要其他结构？感谢您的时间和帮助。

我想核心查询应该更像这样

      SELECT o.order_id
           , op.price
           , op.dt
        FROM orders o 
        JOIN order_price op
          ON op.order_id = o.order_id
        JOIN 
           ( SELECT order_id, MAX(dt) max_dt FROM order_price WHERE dt < '2013-10-26' GROUP BY order_id ) x
          ON x.order_id = op.order_id 
         AND x.max_dt = op.dt;

SELECT o.order_id
     , SUM(op.price) price
     , op.dt
  FROM orders o 
  JOIN order_price op
    ON op.order_id = o.order_id
  JOIN 
     ( SELECT order_id, MAX(dt) max_dt FROM order_price WHERE dt < '2013-10-26' GROUP BY order_id ) x
    ON x.order_id = op.order_id 
   AND x.max_dt = op.dt
 GROUP
    BY order_id,dt
  WITH ROLLUP;

…可以用这种方式重写，以给出总数

SELECT o.order_id
     , SUM(op.price) price
     , op.dt
  FROM orders o 
  JOIN order_price op
    ON op.order_id = o.order_id
  JOIN 
     ( SELECT order_id, MAX(dt) max_dt FROM order_price WHERE dt < '2013-10-26' GROUP BY order_id ) x
    ON x.order_id = op.order_id 
   AND x.max_dt = op.dt
 GROUP
    BY order_id,dt
  WITH ROLLUP;

…还是这样

SELECT o.order_id
     , SUM(op.price) price
     , op.dt
  FROM orders o 
  JOIN order_price op
    ON op.order_id = o.order_id
  JOIN 
     ( SELECT order_id, MAX(dt) max_dt FROM order_price WHERE dt < '2013-10-26' GROUP BY order_id ) x
    ON x.order_id = op.order_id 
   AND x.max_dt = op.dt
 GROUP
    BY order_id,dt
  WITH ROLLUP;

SELECT SUM(price) total 
FROM
 ( SELECT o.order_id
       , op.price
       , op.dt
    FROM orders o 
    JOIN order_price op
      ON op.order_id = o.order_id
    JOIN 
       ( SELECT order_id, MAX(dt) max_dt FROM order_price WHERE dt < '2013-10-26' GROUP BY order_id ) x
      ON x.order_id = op.order_id 
     AND x.max_dt = op.dt
 ) z;

---

…或者只是在应用程序级别提取总数。

在尝试之前，我想知道为什么您需要所有历史变化价格的总和。这些信息的意义是什么？这个查询生成两列，而不是三列。另外，为什么订单的价格会发生变化？订单在时间上是独立的实体，应该有一个固定的价格OP想要所有订单的总和在他们的“当前”价格是的，这是我的错关于第三列-它更虚拟，作为行注释添加在这里。

SELECT o.order_id
     , SUM(op.price) price
     , op.dt
  FROM orders o 
  JOIN order_price op
    ON op.order_id = o.order_id
  JOIN 
     ( SELECT order_id, MAX(dt) max_dt FROM order_price WHERE dt < '2013-10-26' GROUP BY order_id ) x
    ON x.order_id = op.order_id 
   AND x.max_dt = op.dt
 GROUP
    BY order_id,dt
  WITH ROLLUP;