求救：查询问题？急！

[lqhly]

我有一个门卫刷卡系统，表door_inout的结构如下：
id ---员工卡号
datetime_inout ----员工进出时间
flag --------------标识位：1--进厂，2--出厂
如何查询出今天最后一次刷卡为：‘2--出厂’的员工记录。

[friendliu]

select top 1 datetime_inout from door_inout order by datetime_inout desc
go

[friendliu]

select top 1 datetime_inout from door_inout
where flag='2'
order by datetime_inout desc
go

[pengdali]

select top 1 * from door_inout where datediff(day,datetime_inout,getdate())=0 order by datetime_inout desc

[pengdali]

select top 1 * from door_inout where flag='2' and datediff(day,datetime_inout,getdate())=0 order by datetime_inout desc

[playyuer]

select id,max(datetime_inout)
from door_inout
group by id

[sjzmdslxj]

select * from door_inout where
datetime_inout = (select max datetime_inout from door_inout where to_char(datetime_inout,'yyyy-mm-dd')=to_char(sysdate,'yyyy-mm-dd') and flag='2')
and flag='2'

[txlicenhe]

Select * from 表 a
where datetime_inout =
(select max(datetime_inout) from id = a.id where
datediff(day,datetime_inout,getdate()) = 0 )
and flag = '2'

[lqhly]

你们的好象都不对，因为在where中若有flag=2后，都是‘出厂’的记录，而我需要的是今天‘出厂’和‘进厂’所有刷卡的最后一次刷卡为：‘2--出厂’的记录。

[pengdali]

我有一个门卫刷卡系统，表door_inout的结构如下：
id ---员工卡号
datetime_inout ----员工进出时间
flag --------------标识位：1--进厂，2--出厂
如何查询出今天最后一次刷卡为：‘2--出厂’的员工记录。



select * from door_inout tem where flag='2--出厂' and datetime_inout=(
select max(datetime_inout) from door_inout where datediff(day,datetime_inout,getdate())=0 group by id having id=tem.id)

[pengdali]

select * from door_inout tem where flag='2--出厂' and datetime_inout=(
select max(datetime_inout) from door_inout where datediff(day,datetime_inout,getdate())=0 and id=tem.id)

[nadylu]

select id,MAX(datetime_inout)
from door_inout
where flag='2'