usedb go createtabletablel ( idintidentity(1,1)notnull, propertyvarchar(20)notnull, datedatetimenotnull ) go insertintotablelvalues('CSD001','2012-12-12:12:10') insertintotablelvalues('CSD001','2012-12-12:12:13') insertintotablelvalues('CS
use db
go
create table tablel
(
id int identity(1,1) not null,
property varchar(20) not null,
date datetime not null
)
go
insert into tablel values('CSD001','2012-12-12:12:10')
insert into tablel values('CSD001','2012-12-12:12:13')
insert into tablel values('CSD001','2012-12-12:12:14')
insert into tablel values('CSD001','2012-12-12:12:16')
insert into tablel values('CSD002','2012-12-12 12:13:14')
insert into tablel values('CSD002','2012-12-12 12:13:16')
insert into tablel values('CSD002','2012-12-12 12:13:18')
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3
insert into tablel values('CSD002','2012-12-12 12:13:45)
insert into tablel values('CSD003','2012-12-12 12:13:14')
insert into tablel values('CSD003','2012-12-12 12:13:16')
insert into tablel values('CSD003','2012-12-12 12:13:18')
insert into tablel values('CSD003','2012-12-12 12:13:45)
insert into tablel values('CSD004’,'2012-12-12 12:13:14')
insert into tablel values('CSD004','2012-12-12 12:13:16')
insert into tablel values('CSD004','2012-12-12 12:13:18')
insert into tablel values('CSD004','2012-12-12 12:13:45)
查询每个属性最小两个值;
第一种方法为:
Select * from (select row_number() over(patittion by property order by a.date asc) as rowIndex, * from tablel as a where property in ( select distict(property) from tablel )) t where rowIndex
第二种方法为:
或者 select * from tablel as a where property in (select top 2 Property from tablel where a.property=property order by a.date asc)
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