Mysql 按问题进行计数和分组

Mysql 按问题进行计数和分组,mysql,count,group-by,Mysql,Count,Group By,我有那张桌子: 论坛: _____________________________________________________________ |match_static_id| comment | timpstamp | user_id | |_______________|___________|______________________|__________| | 1 | Hi | 2013-07-10 12:15:

我有那张桌子:

论坛:

 _____________________________________________________________
|match_static_id| comment   | timpstamp            | user_id  |
|_______________|___________|______________________|__________|
|  1            |  Hi       | 2013-07-10 12:15:03  |     2    |
|  1            |  Hello    | 2013-07-09 12:14:44  |     1    | 
|_______________|___________|______________________|__________|
工作查询是:

select forum.match_static_id, 
       count(forum.match_static_id) 'comment_no' 
Group By forum.match_static_id 
但如果我想要:

select forum.match_static_id, 
   count(forum.match_static_id) 'comment_no',
   forum.timestamp
Group By forum.match_static_id 
它将给出与前一个查询相同的结果,但每个记录的值都是timestamp

我希望此值是可以完成的最新时间戳?

只需使用max()函数即可

select forum.match_static_id, 
   count(forum.match_static_id) 'comment_no',
   max(forum.timestamp)
Group By forum.match_static_id
以下是可用的列表和说明。

这个怎么样:

select forum.match_static_id, 
count(forum.match_static_id) 'comment_no',
max(forum.timestamp)
Group By forum.match_static_id