mysql group by和max

rpppsulh  于 2021-06-21  发布在  Mysql
关注(0)|答案(2)|浏览(371)

这个问题在这里已经有答案了

检索每个组中的最后一条记录-mysql(29个答案)
两年前关门了。
我在mysql中有一个表:

+----+------+------------+-------+
| id | code |    date    | value |
+----+------+------------+-------+
| 1  |   3  | 2016-01-01 |   3   |
| 2  |   3  | 2016-01-02 |   4   |
| 3  |   3  | 2016-03-01 |   6   |
| 4  |   3  | 2016-06-06 |   5   |
| 5  |   8  | 2016-01-01 |   1   |
| 6  |   8  | 2016-09-09 |   3   |
+----+------+------------+-------+

我想退回这样一张table:

+------+------------+-------+
| code |    date    | value |
+------+------------+-------+
|  3   | 2016-06-06 |   5   |
|  8   | 2016-09-09 |   3   |
+------+------------+-------+

我的服务器设置是:


**MySQL**

Server: localhost via TCP/IP
Server version: 5.5.16
Protocol version: 10
User: root@localhost
MySQL charset: UTF-8 Unicode (utf8)

**Web server**

Apache/2.2.21 (Win32) mod_ssl/2.2.21 OpenSSL/1.0.0e PHP/5.3.8
MySQL client version: mysqlnd 5.0.8-dev - 20102224 - $Revision: 310735 $

我尝试了这个脚本,但没有成功:

SELECT *
FROM tbl_mysql
WHERE date IN (SELECT MAX(date) FROM tbl_mysql GROUP BY code)

如何更改脚本以在服务器版本上工作?谢谢您!

8dtrkrch

8dtrkrch1#

http://sqlfiddle.com/#!9/4cf933/2号

SELECT t.*
FROM tbl_mysql t
LEFT JOIN tbl_mysql t2
ON t.code = t2.code
   AND t.date<t2.date
WHERE t2.id IS NULL
9lowa7mx

9lowa7mx2#

您可以应用self-join;

select t1.* from table1 t1 inner join 
(select code,max(date) maxDate from table1 group by code) t2
ON t1.code = t2.code and t1.date = t2.maxDate

演示

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