mysql - 时间和日期字段与 ID 字段不同步

Question

我表中的数据

    item
item_id  name
1        ball
2        cap
3        bat

    order
order_id  date         time
1         06/01/2013   15:12
2         12/01/2013   11:10
3         06/01/2013   23:10
4         23/01/2013   10:55

    orderform
order_id item_id quantity
1        1       2
1        3       4
2        1       1
3        2       3
3        1       2
3        3       1
4        1       2

目前我正在使用以下 sql 查询:

 SELECT
  order_id, 
  group_concat(txt) AS txt,
  date,
  time
FROM (
    SELECT 
      orderform.order_id AS order_id,
      order.date AS date,
      order.time AS time,
      CONCAT(orderform.quantity, ' x ',item.name) AS txt
    FROM order orderform
    LEFT JOIN item ON orderform.item_id = item.item_id
) AS baseview
GROUP BY order_id

我明白了，日期和时间未与 id 同步。

order_id  name                      date         time
1         2 x ball,4 x bat          06/01/2013   15:12
2         ball                      06/01/2013   23:10
3         3 x cap,2 x ball,bat      06/01/2013   15:12
4         2 x ball                  06/01/2013   15:12

它应该是这样的。我应该在此查询中仅针对时间和日期做另一个子选择吗？感谢您的帮助。

          order_id  name             date         time
1         2 x ball,4 x bat          06/01/2013   15:12
2         ball                      12/01/2013   11:10
3         3 x cap,2 x ball,bat      06/01/2013   23:10
4         2 x ball                  23/01/2013   10:55

感谢您的帮助。

Answer 1

实际上，即使不使用子查询，您也可以获得您想要的结果。

SELECT  a.order_ID,
        GROUP_CONCAT(CONCAT(b.quantity, ' x ',c.name) SEPARATOR ', ') ItemName,
        MAX(a.date) date,
        MAX(a.time) time
FROM    `order` a
        INNER JOIN orderform b
            ON a.order_id  = b.order_id 
        INNER JOIN item c
            ON b.item_id = c.item_id 
GROUP   BY a.order_ID

• SQLFiddle Demo