Question

无法理解如何选择：表结构：

id name value date
1 ivan    2    2010-01-01
2 ivan    3    2010-05-08
3 ivan    1    2009-04-14
4 sasha   2    2011-11-11
5 sasha   9    2012-04-04

如何获得？：

name value(in last time)
ivan  3
sasha 9

Answer 1

这是未经测试的，但应该有效：

SELECT
    name,
    MAX(value)
FROM
    structure
GROUP BY
    name

Answer 2

SELECT DISTINCT name, value FROM table ORDER BY date DESC

这就是我目前对你目前描述的理解。

Answer 3

这样的事情：

SELECT
    MAX(value),
    name
FROM
    Table
GROUP BY
    name

Answer 4

此查询应该有效

select f.name, f.value, f.date
from (
   select id,name,max(date) as dat from tableName group by name
) as x inner join tableName as f on f.name = x.name and f.date = x.dat;

MySQL狡猾的选择

4 个答案: