一个相当快的方法如下。

SELECT * 
FROM messages a
WHERE Id = (SELECT MAX(Id) FROM messages WHERE a.Name = Name)

结果

Id  Name    Other_Columns
3   A   A_data_3
5   B   B_data_2
6   C   C_data_1

一个相当快的方法如下。

SELECT * 
FROM messages a
WHERE Id = (SELECT MAX(Id) FROM messages WHERE a.Name = Name)

结果

Id  Name    Other_Columns
3   A   A_data_3
5   B   B_data_2
6   C   C_data_1

你也可以从这里看。

http://sqlfiddle.com/ !9 / ef42b / 9

第一个解决方案

SELECT d1.ID,Name,City FROM Demo_User d1
INNER JOIN
(SELECT MAX(ID) AS ID FROM Demo_User GROUP By NAME) AS P ON (d1.ID=P.ID);

第二个解决方案

SELECT * FROM (SELECT * FROM Demo_User ORDER BY ID DESC) AS T GROUP BY NAME ;

SELECT * FROM table_name WHERE primary_key IN (SELECT MAX(primary_key) FROM table_name GROUP BY column_name )

使用子查询返回正确的分组，因为您已经完成了一半。

试试这个:

select
    a.*
from
    messages a
    inner join 
        (select name, max(id) as maxid from messages group by name) as b on
        a.id = b.maxid

如果它不是id，你想要的最大值:

select
    a.*
from
    messages a
    inner join 
        (select name, max(other_col) as other_col 
         from messages group by name) as b on
        a.name = b.name
        and a.other_col = b.other_col

通过这种方式，可以避免在子查询中进行相关子查询和/或排序，这往往非常缓慢/低效。

这是另一个没有子查询的选项。

本解决方案使用MySQL的LAST_VALUE窗口函数，利用窗口函数框架提供MySQL工具。

SELECT DISTINCT 
    LAST_VALUE(Id)            
        OVER(PARTITION BY Name 
             ORDER     BY Id 
             ROWS BETWEEN 0 PRECEDING 
                      AND UNBOUNDED FOLLOWING),
    Name,
    LAST_VALUE(Other_Columns)            
        OVER(PARTITION BY Name 
             ORDER     BY Id 
             ROWS BETWEEN 0 PRECEDING 
                      AND UNBOUNDED FOLLOWING)
FROM   
    tab

在这里试试。