日期:2014-05-19  浏览次数:20490 次

实用但 好几个人没解决的SQL 查询
select   min(enddate)   enddate   from   hm_em_contracts   C   where   C.em_id= '111222 '
group   by   C.em_id

这个查询没问题,但我还想多显示ID   这个字段,我写成这样
select   min(C.id))   ID   ,min(enddate)   enddate   from   hm_em_contracts   C   where   C.em_id= '111222 '
group   by   C.em_id

语句通过,但这个ID不是对应相关记录的值。   如下
        id         enddate
          5         2003-06-01
但应在数据库中的ID   是     7

怎   么解决?




------解决方案--------------------
select min(C.id)) ID ,min(enddate) enddate from hm_em_contracts C where C.em_id= '111222 '
group by C.em_id
==================================================
select C.id ID ,min(enddate) enddate from hm_em_contracts C where C.em_id= '111222 '
group by C.em_id
改成这样就可以了


------解决方案--------------------
select C.id ID ,min(enddate) enddate from hm_em_contracts C where C.em_id= '111222 '
group by C.em_id,C.id

------解决方案--------------------
这样试试
update hm_em_contracts set serialNO=C.code+ '01 '
from
(select min(enddate) enddate,em_id
from hm_em_contracts C group by em_id) T
inner join hm_employees C on C.em_id=T.em_id and c.enddate=t.enddate
where hm_em_contracts.id=C.id
------解决方案--------------------
d 前面 的括号里面没有 select 不是一个结果集,所以不能加别名
这样试试
update hm_em_contracts set serialNO= '01 '
from
(select C.em_id, min(enddate) enddate
from hm_em_contracts C group by C.em_id) b
inner join hm_em_contracts a
on a.em_id=b.em_id and a.enddate=b.enddate
where a.em_id is not null

不是要找 ID嘛? 最后一句也可以用 where a.id is not null