sqlserver 问题求指导

[jujian19881004]

proj_sid plan_version_sid registerdate
9D82766E-67BB-460D-B2AB-29C1350B9F60 1 2015-12-7
9D82766E-67BB-460D-B2AB-29C1350B9F60 2 2015-12-4
9D82766E-67BB-460D-B2AB-29C1350B9F60 3 2015-12-1
114A8783-BCA2-4A58-8814-C2A977BF9E6F 11 2015-08-04
114A8783-BCA2-4A58-8814-C2A977BF9E6F 21 2015-08-05

想用视图取出，project_sid 唯一 ，录入日期最小的记录，应该怎么取，求各位大神指导。
取出来的效果为：
proj_sid plan_version_sid registerdate
9D82766E-67BB-460D-B2AB-29C1350B9F60 3 2015-12-1
114A8783-BCA2-4A58-8814-C2A977BF9E6F 11 2015-08-04

[不穿内裤的超人]

with cte(project_sid,plan_version_sid,registerdate) as (
select '9D82766E-67BB-460D-B2AB-29C1350B9F60',                       1                                 ,'2015-12-7' union 
select '9D82766E-67BB-460D-B2AB-29C1350B9F60',                        2                                ,'2015-12-4' union 
select '9D82766E-67BB-460D-B2AB-29C1350B9F60',                       3                                ,'2015-12-1' union 
select '114A8783-BCA2-4A58-8814-C2A977BF9E6F',                      	   11	                             ,'2015-08-04' union 
select '114A8783-BCA2-4A58-8814-C2A977BF9E6F',	                        21	                             ,'2015-08-05')
select cte.* from cte,(
select project_sid,min(registerdate)as registerdate from cte group by project_sid) a
where cte.project_sid=a.project_sid and cte.registerdate=a.registerdate

[等不到来世]

select * from tb t
where not exists(select 1 from tb where project_sid=t.project_sid and registerdate<t.registerdate)

[jienyuan]

select min(registerdate) from 你的表名 where proj_sid in (select proj_sid from (select proj_sid,count(proj_sid) from 你的表名 group by proj_sid having count(proj_sid) = 1) a)

[道素]

with t as (
select '9D82766E-67BB-460D-B2AB-29C1350B9F60' AS project_sid,1 AS plan_version_sid,'2015-12-7' AS registerdate union 
select '9D82766E-67BB-460D-B2AB-29C1350B9F60',2 ,'2015-12-4' union 
select '9D82766E-67BB-460D-B2AB-29C1350B9F60',3  ,'2015-12-1' union 
select '114A8783-BCA2-4A58-8814-C2A977BF9E6F',11 ,'2015-08-04' union 
select '114A8783-BCA2-4A58-8814-C2A977BF9E6F',21 ,'2015-08-05'
)
SELECT * FROM (
   select t.*, ROW_NUMBER()OVER (PARTITION BY project_sid ORDER BY registerdate) as SeqNo from t
) tt WHERE tt.SeqNo=1

如果project_sid,registerdate相同的值存在多行记录，还需要其他字典排序，都放到ROW_NUMBER()OVER (PARTITION BY project_sid ORDER BY register date)中