MySQL查询选择具有最新created_at日期的行到列

我正在尝试创建一个查询，在该查询中我想将我的行转换为具有panel_name GROUP BY行的列，并按单个日期的最后created_at条进行排列。我的数据以列格式显示，但未显示特定日期。我尝试了多个查询，但没有对结果进行游戏。这是我的表结构的样子。

+--------------+------------------+------+-----+---------+----------------+
| Field        | Type             | Null | Key | Default | Extra          |
+--------------+------------------+------+-----+---------+----------------+
| id           | int(10) unsigned | NO   | PRI | NULL    | auto_increment |
| panel_name   | varchar(191)     | YES  |     | NULL    |                |
| panel_number | varchar(191)     | YES  |     | NULL    |                |
| display_from | date             | YES  |     | NULL    |                |
| open_time    | varchar(191)     | YES  |     | NULL    |                |
| close_time   | varchar(191)     | YES  |     | NULL    |                |
| created_at   | timestamp        | YES  |     | NULL    |                |
| updated_at   | timestamp        | YES  |     | NULL    |                |
| deleted_at   | timestamp        | YES  |     | NULL    |                |
+--------------+------------------+------+-----+---------+----------------+

这是我当前数据的样子：

+-----+-------------------+--------------+--------------+-----------+------------+---------------------+---------------------+---------------------+
| id  | panel_name        | panel_number | display_from | open_time | close_time | created_at          | updated_at          | deleted_at          |
+-----+-------------------+--------------+--------------+-----------+------------+---------------------+---------------------+---------------------+
| 447 | TARA MUMBAI DAY   | 123-1*-***   | NULL         | NULL      | NULL       | 2019-11-13 10:31:27 | 2019-11-13 10:31:27 | NULL                |
| 446 | TIME              | 123-**-***   | NULL         | NULL      | NULL       | 2019-11-13 10:22:15 | 2019-11-13 10:22:15 | NULL                |
| 445 | TIME              | ***-**-***   | NULL         | NULL      | NULL       | 2019-11-11 18:00:01 | 2019-11-11 18:33:29 | 2019-11-11 18:33:29 |
| 444 | TIME              | ***-**-***   | NULL         | NULL      | NULL       | 2019-11-11 17:59:58 | 2019-11-11 18:33:32 | 2019-11-11 18:33:32 |
| 443 | TARA MUMBAI DAY   | 128-74-446   | NULL         | NULL      | NULL       | 2019-11-11 17:51:50 | 2019-11-11 17:51:50 | NULL                |
| 442 | TARA MUMBAI DAY   | 128-74-446   | NULL         | NULL      | NULL       | 2019-11-11 17:51:30 | 2019-11-11 17:51:30 | NULL                |
| 441 | TARA MUMBAI DAY   | 128-74-446   | NULL         | NULL      | NULL       | 2019-11-11 17:51:15 | 2019-11-11 17:51:15 | NULL                |
| 440 | TARA MUMBAI DAY   | 128-74-446   | NULL         | NULL      | NULL       | 2019-11-11 17:50:40 | 2019-11-11 17:50:40 | NULL                |
| 439 | TARA MUMBAI DAY   | 128-74-***   | NULL         | NULL      | NULL       | 2019-11-11 17:49:17 | 2019-11-11 17:49:17 | NULL                |
| 438 | TARA MUMBAI DAY   | 128-7-***    | NULL         | NULL      | NULL       | 2019-11-11 17:48:03 | 2019-11-11 17:48:03 | NULL                |
| 437 | TARA MUMBAI DAY   | 128-7*-***   | NULL         | NULL      | NULL       | 2019-11-11 17:46:22 | 2019-11-11 17:46:22 | NULL                |
| 436 | TARA MUMBAI DAY   | 128-**-***   | NULL         | NULL      | NULL       | 2019-11-11 17:45:11 | 2019-11-11 17:45:11 | NULL                |
| 435 | TIME              | 1**-**-***   | NULL         | NULL      | NULL       | 2019-11-11 17:44:43 | 2019-11-11 17:44:43 | NULL                |
| 434 | TIME              | 1**-**-***   | NULL         | NULL      | NULL       | 2019-11-11 17:43:24 | 2019-11-11 17:43:24 | NULL                |
| 433 | TIME              | 1**-**-***   | NULL         | NULL      | NULL       | 2019-11-11 17:43:11 | 2019-11-11 17:43:11 | NULL                |
| 432 | TARA MUMBAI NIGHT | 700-74-789   | NULL         | NULL      | NULL       | 2019-11-11 17:41:53 | 2019-11-11 17:41:53 | NULL                |
| 431 | TARA MUMBAI DAY   | 700-74-789   | NULL         | NULL      | NULL       | 2019-11-11 17:41:36 | 2019-11-11 17:41:36 | NULL                |
| 430 | MILAN DAY         | 700-74-789   | NULL         | NULL      | NULL       | 2019-11-11 17:41:09 | 2019-11-11 17:41:09 | NULL                |
| 429 | MILAN DAY         | 700-74-789   | NULL         | NULL      | NULL       | 2019-11-11 17:40:52 | 2019-11-11 17:40:52 | NULL                |
| 428 | MILAN DAY         | 700-74-789   | NULL         | NULL      | NULL       | 2019-11-11 17:40:35 | 2019-11-11 17:40:35 | NULL                |
| 427 | MILAN DAY         | 700-74-789   | NULL         | NULL      | NULL       | 2019-11-11 17:40:20 | 2019-11-11 17:40:20 | NULL                |
| 426 | MILAN DAY         | 700-74-789   | NULL         | NULL      | NULL       | 2019-11-11 17:39:06 | 2019-11-11 17:39:06 | NULL                |
| 425 | MILAN DAY         | 700-74-789   | NULL         | NULL      | NULL       | 2019-11-11 17:38:58 | 2019-11-11 17:38:58 | NULL                |
| 424 | MILAN DAY         | 700-7*-***   | NULL         | NULL      | NULL       | 2019-11-11 17:34:43 | 2019-11-11 17:34:43 | NULL                |
| 423 | MILAN DAY         | 700-7*-***   | NULL         | NULL      | NULL       | 2019-11-11 17:34:20 | 2019-11-11 17:34:20 | NULL                |
| 422 | MILAN DAY         | 700-7*-***   | NULL         | NULL      | NULL       | 2019-11-11 17:33:56 | 2019-11-11 17:33:56 | NULL                |
| 421 | TARA MUMBAI DAY   | 477-80-244   | NULL         | NULL      | NULL       | 2019-11-11 17:23:18 | 2019-11-11 17:23:18 | NULL                |
| 420 | TARA MUMBAI DAY   | 477-80-244   | NULL         | NULL      | NULL       | 2019-11-11 17:22:56 | 2019-11-11 17:25:47 | 2019-11-11 17:25:47 |
| 419 | TARA MUMBAI DAY   | 477-80-244   | NULL         | NULL      | NULL       | 2019-11-11 17:22:45 | 2019-11-11 17:25:44 | 2019-11-11 17:25:44 |
| 418 | TARA MUMBAI DAY   | 477-80-***   | NULL         | NULL      | NULL       | 2019-11-11 17:19:25 | 2019-11-11 17:19:25 | NULL                |
+-----+-------------------+--------------+--------------+-----------+------------+---------------------+---------------------+---------------------+

这就是我要如何查看结果

 +--+-------------------+------------+-----------+-------------------+------------+
 |  | TARA MUMBAI DAY   | TIME       | MILAN DAY | TARA MUMBAI NIGHT | created_at |
 +--+-------------------+------------+-----------+-------------------+------------+
      123-1*-***         123-**-***       NULL          NULL           2019-11-13
      128-74-446         1**-**-***    700-74-789     700-74-789       2019-11-11

因此，这是到目前为止我已经尝试了多少，但剂量似乎表明了我想要的结果。

SELECT
    max(r0.id),r1.panel_name AS "TIME",r2.panel_name AS "TARA MUMBAI DAY",r3.panel_name AS "MILAN DAY",r4.panel_name AS "TARA MUMBAI NIGHT",r0.Dateonly
FROM
      (SELECT   
              id,panel_name,panel_number,DATE(created_at) as Dateonly
        FROM 
              foduu_potresult
        ) r0
        LEFT JOIN foduu_potresult r1 
              ON r1.id = r0.id   AND r1.panel_name = 'TIME'
      LEFT JOIN foduu_potresult r2 
              ON r2.id = r0.id   AND r2.panel_name = 'TARA MUMBAI DAY'
      LEFT JOIN foduu_potresult r3 
              ON r3.id = r0.id   AND r3.panel_name = 'MILAN DAY'
      LEFT JOIN foduu_potresult r4 
              ON r4.id = r0.id   AND r4.panel_name = 'TARA MUMBAI NIGHT'
              GROUP BY 
              r0.Dateonly
ORDER BY 
      r0.id DESC

对这种查询有什么建议吗？我如何显示适当的结果。

您可以使用相关子查询来过滤表，并保留created_at的每个panel_name和日期created_at的最新select max(case when panel_name = 'TARA MUMBAI DAY' then panel_number end ) `TARA MUMBAI DAY`,max(case when panel_name = 'TIME' then panel_number end ) `TIME`,max(case when panel_name = 'MILAN DAY' then panel_number end ) `MILAN DAY`,max(case when panel_name = 'TARA MUMBAI NIGHT' then panel_number end ) `TARA MUMBAI NIGHT`,date(created_at) created_at from mytable t where created_at = ( select max(t1.created_at) from mytable t1 where date(t1.created_at) = date(t.created_at) and t1.panel_name = t.panel_name ) group by date(created_at)的记录。然后，您可以使用条件聚合来调整结果：

localStorage.getItem("token");

Demo on DB Fiddlde

TARA MUMBAI DAY | TIME       | MILAN DAY  | TARA MUMBAI NIGHT | created_at
:-------------- | :--------- | :--------- | :---------------- | :---------
128-74-446      | ***-**-*** | 700-74-789 | 700-74-789        | 2019-11-11
123-1*-***      | 123-**-*** | null       | null              | 2019-11-13

MySQL查询选择具有最新created_at日期的行到列

fj9921 回答：MySQL查询选择具有最新created_at日期的行到列

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