Question

我有这张桌子

id|name|number|date
1|peter|2|2017-09-18
2|peter|1|2017-10-03
3|james|4|2017-09-05
4|james|1|2017-10-10
5|james|0|2017-10-15
6|kate|4|2017-09-16
7|kate|2|2017-10-17

我想为每个人选择最新的行（具有最新日期的行）。结果看起来像

2|peter|1|2017-10-03
5|james|0|2017-10-15
7|kate|2|2017-10-17

哪个MYSQL查询可以做到这一点？

类似的东西：

SELECT id, name, number, date 
FROM table 
GROUP BY id, name, number, date 
HAVING date the latest

Answer 1

select t1.* from table t1, (select t2.name name2, max(t2.date) 
date2 from table t2 group by t2.name) t3 where t1.name = t3.name2 and t1.date = t3.date2

Answer 2

SELECT * FROM persons WHERE name='someone' order by date desc limit 1

这适用于按指定名称选择最新实体。

SELECT * FROM persons GROUP BY name, date ORDER BY date DESC

我用手机写的这个，可能是错的，但它的概念是正确的。

Answer 3

MariaDB [test]> select * from stack s1 where s1.d = (select max(s2.d) 
from stack s2 where s2.name = s1.name);
+------+-------+------+------------+
| id   | name  | num  | d          |
+------+-------+------+------------+
|    2 | peter |    1 | 2017-10-03 |
|    5 | james |    0 | 2017-10-15 |
|    7 | kate  |    2 | 2017-10-17 |
+------+-------+------+------------+
3 rows in set (0.00 sec)

对于大型数据集，请不要忘记将索引添加到＆＃39; name＆＃39;并且＆＃39; d＆＃39;列。

MySQL Query，我想为每个人选择最新的行

3 个答案: