表
index userid workid time
1 1 1 2013-07-23 12:38:10
2 2 2 2013-07-23 12:38:11
3 3 3 2013-07-23 12:38:12
4 1 4 2013-07-23 12:38:13
5 2 5 2013-07-23 12:38:14
6 3 6 2013-07-23 12:38:15
想要查出每个人最晚那条记录 如
4 1 4 2013-07-23 12:38:13
5 2 5 2013-07-23 12:38:14
6 3 6 2013-07-23 12:38:15
求搭救
sql?查询?
------解决方案--------------------
select * from 表 a
where time=(select max(time) from 表 where a.userid=userid)
------解决方案--------------------
select a.*
from tb a
inner join (select userid,max(time) as time from tb group by userid)b
on a.userid=b.userid and a.time=b.time
------解决方案--------------------
create table tb([index] int, userid int,workid int,[time] datetime)
insert into tb
select 1,1,1,'2013-07-23 12:38:10'
union all select 2,2,2,'2013-07-23 12:38:11'
union all select 3,3,3,'2013-07-23 12:38:12'
union all select 4,1,4,'2013-07-23 12:38:13'
union all select 5,2,5,'2013-07-23 12:38:14'