Mysql 批次和出价的SQL查询：查找用户是否出价最高_Mysql_Sql_Select_Eloquent

Mysql 批次和出价的SQL查询：查找用户是否出价最高

mysql sql select

Mysql 批次和出价的SQL查询：查找用户是否出价最高,mysql,sql,select,eloquent,Mysql,Sql,Select,Eloquent,我正在建立一个拉威尔拍卖应用程序。我有一张抽签表和一张投标表地段表： mysql> select id, lot_name, created_at, updated_at from lots; +----+----------+---------------------+---------------------+ | id | lot_name | created_at | updated_at | +----+----------+--------

我正在建立一个拉威尔拍卖应用程序。我有一张抽签表和一张投标表

地段表：

mysql> select id, lot_name, created_at, updated_at from lots;
+----+----------+---------------------+---------------------+
| id | lot_name | created_at          | updated_at          |
+----+----------+---------------------+---------------------+
|  1 | Lot 1    | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
|  2 | Lot 2    | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
|  3 | Lot 3    | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
|  4 | Lot 4    | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
|  5 | Lot 5    | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
|  6 | Lot 6    | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
|  7 | Lot 7    | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
|  8 | Lot 8    | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
|  9 | Lot 9    | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
| 10 | Lot 10   | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
| 11 | Lot 11   | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
| 12 | Lot 12   | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
| 13 | Lot 13   | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
| 14 | Lot 14   | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
| 15 | Lot 15   | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
| 16 | Lot 16   | 2016-06-09 14:23:58 | 2016-06-09 14:23:58 |
+----+----------+---------------------+---------------------+

投标表格：

mysql> select * from bids;
+----+--------+---------+-----------+---------------------+---------------------+
| id | lot_id | user_id | bid_value | created_at          | updated_at          |
+----+--------+---------+-----------+---------------------+---------------------+
|  1 |      1 |       2 | 100       | 2016-06-01 11:14:15 | 2016-06-09 14:23:59 |
|  2 |      1 |       2 | 150       | 2016-06-01 13:19:02 | 2016-06-09 14:23:59 |
|  3 |      1 |       3 | 160       | 2016-06-02 09:02:35 | 2016-06-09 14:23:59 |
|  4 |      1 |       2 | 180       | 2016-06-02 12:25:16 | 2016-06-09 14:23:59 |
|  5 |      2 |       2 | 100       | 2016-06-01 09:26:17 | 2016-06-09 14:23:59 |
|  6 |      2 |       3 | 150       | 2016-06-01 10:14:15 | 2016-06-09 14:23:59 |
|  7 |      2 |       2 | 160       | 2016-06-01 11:35:09 | 2016-06-09 14:23:59 |
|  8 |      3 |       3 | 180       | 2016-06-04 11:14:15 | 2016-06-09 14:23:59 |
|  9 |      1 |       3 | 200       | 2016-06-03 19:29:56 | 2016-06-09 14:23:59 |
| 10 |      3 |       2 | 250       | 2016-06-04 23:14:15 | 2016-06-09 14:23:59 |
| 11 |      4 |       2 | 500       | 2016-06-03 09:16:39 | 2016-06-09 14:23:59 |
| 12 |      1 |       3 | 230       | 2016-06-01 11:14:15 | 2016-06-09 14:23:59 |
| 13 |      1 |       2 | 250       | 2016-06-01 11:14:15 | 2016-06-09 14:23:59 |
| 14 |      3 |       2 | 300       | 2016-06-05 02:14:15 | 2016-06-09 14:23:59 |
| 15 |      2 |       3 | 180       | 2016-06-01 20:44:15 | 2016-06-09 14:23:59 |
| 16 |      4 |       2 | 600       | 2016-06-04 08:59:15 | 2016-06-09 14:23:59 |
| 17 |      1 |       3 | 300       | 2016-06-03 17:20:30 | 2016-06-09 14:23:59 |
| 18 |      1 |       3 | 350       | 2016-06-04 18:04:55 | 2016-06-09 14:23:59 |
| 19 |      7 |       2 | 160       | 2016-06-02 22:24:02 | 2016-06-09 14:23:59 |
| 20 |      1 |       3 | 400       | 2016-06-05 07:00:27 | 2016-06-09 14:23:59 |
| 21 |      8 |       3 | 100       | 2016-06-02 11:58:29 | 2016-06-09 14:23:59 |
| 22 |      1 |       3 | 450       | 2016-06-05 10:09:06 | 2016-06-09 14:23:59 |
| 23 |      1 |       2 | 480       | 2016-06-05 14:12:15 | 2016-06-09 14:23:59 |
| 24 |      5 |       2 | 1000      | 2016-06-02 13:38:34 | 2016-06-09 14:23:59 |
| 25 |      1 |       2 | 525       | 2016-06-05 20:39:29 | 2016-06-09 14:23:59 |
| 26 |      1 |       3 | 600       | 2016-06-05 23:59:50 | 2016-06-09 14:23:59 |
| 27 |      6 |       2 | 1000      | 2016-06-01 07:00:02 | 2016-06-09 14:23:59 |
| 28 |      6 |       3 | 1200      | 2016-06-04 23:14:56 | 2016-06-09 14:23:59 |
+----+--------+---------+-----------+---------------------+---------------------+

关系标段投标：一个标段可以包含多个投标（来自多个用户），每个投标仅属于一个标段和一个用户

我的目标是创建一个视图，显示用户是否对给定批次出价最高。我将在一个表中用绿色/红色行表示（如果用户对该批次出价最高，则为绿色）

理想情况下，我希望实现以下目标（因此我可以创建一个Laravel查询，并将其发送到视图以在阵列上循环）

我要说的是：

mysql> select lot_id, max(bid_value) as 'highest value' from bids group by lot_id;
+--------+---------------+
| lot_id | highest value |
+--------+---------------+
|      1 | 600           |
|      2 | 180           |
|      3 | 300           |
|      4 | 600           |
|      5 | 1000          |
|      6 | 1200          |
|      7 | 160           |
|      8 | 100           |
+--------+---------------+

以及：

mysql> select lot_id, max(bid_value) as user_highest_bid from bids where user_id=2 group by lot_id;
+--------+------------------+
| lot_id | user_highest_bid |
+--------+------------------+
|      1 | 525              |
|      2 | 160              |
|      3 | 300              |
|      4 | 600              |
|      5 | 1000             |
|      6 | 1000             |
|      7 | 160              |
+--------+------------------+

我如何将这些信息结合起来，以获得我想要的表格，从而包括额外的批次信息，并且仅包括用户已出价的这些批次

----编辑---- 添加来自Mureinik的正确答案（有细微更改）：

您需要在此处进行两次查询-一次查询标段详细信息，另一次查询汇总出价。这里一个巧妙的技巧是使用case语句来计算某个用户的最大出价，因此您只需要一个聚合查询

在这个查询中，我假设您只想要用户实际出价的结果。如果不是这样，只需在连接中删除

notnull

条件：

SELECT lot.*, b.*
FROM   lots
JOIN   (SELECT   lot_id, 
                 2 AS user_id, 
                 MAX(bid_value) AS highest_value,
                 MAX(CASE user_id WHEN 2 THEN bid_value END) AS highest_bid
        FROM     bids
        GROUP BY lot_id) b ON lot.lot_id = b.lot_id AND highest_bid IS NOT NULL

这太棒了！非常感谢。我做了一些较小的修改，编辑了上面的问题，以包含带有小修改的版本

mysql> SELECT lots.*, b.*
    ->        FROM   lots
    ->        JOIN   (SELECT   lot_id,
    ->                         2 AS user_id,
    ->                         MAX(bid_value) AS highest_value,
    ->                         MAX(CASE user_id WHEN 2 THEN bid_value END) AS highest_bid
    ->                FROM     bids
    ->                GROUP BY lot_id) b ON lots.id = b.lot_id AND highest_bid IS NOT NULL;

SELECT lot.*, b.*
FROM   lots
JOIN   (SELECT   lot_id, 
                 2 AS user_id, 
                 MAX(bid_value) AS highest_value,
                 MAX(CASE user_id WHEN 2 THEN bid_value END) AS highest_bid
        FROM     bids
        GROUP BY lot_id) b ON lot.lot_id = b.lot_id AND highest_bid IS NOT NULL