我每月通讯的一个非常简单的数据集:
id | Name | PublishDate | IsActive
1 | Newsletter 1 | 10/15/2012 | 1
2 | Newsletter 2 | 11/06/2012 | 1
3 | Newsletter 3 | 12/15/2012 | 0
4 | Newsletter 4 | 1/19/2012 | 0
等等。
该PublishDate是独一无二的。
结果(基于上面):
id | Name | PublishDate | IsActive
2 | Newsletter 2 | 11/06/2012 | 1
我要的是非常简单的。 我只是想在1个通讯是IsActive和PublishDate = MAX(PublishDate)。
select top 1 * from newsletters where IsActive = 1 order by PublishDate desc
您可以使用row_number()
select id, name, publishdate, isactive
from
(
select id, name, publishdate, isactive,
row_number() over(order by publishdate desc) rn
from table1
where isactive = 1
) src
where rn = 1
请参阅SQL拨弄演示
你甚至可以使用选择的子查询max()
日期:
select t1.*
from table1 t1
inner join
(
select max(publishdate) pubdate
from table1
where isactive = 1
) t2
on t1.publishdate = t2.pubdate
请参阅SQL拨弄演示
CREATE TABLE Tmax(Id INT,NAME VARCHAR(15),PublishedDate DATETIME,IsActive BIT)
INSERT INTO Tmax(Id,Name,PublishedDate,IsActive)
VALUES(1,'Newsletter 1','10/15/2012',1),(2,'Newsletter 2','11/06/2012',1),(3,'Newsletter 3','12/15/2012',0),(4,'Newsletter 4','1/19/2012',0)
SELECT * FROM Tmax
SELECT t.Id
,t.NAME
,t.PublishedDate
,t.IsActive
FROM Tmax AS t
WHERE PublishedDate=
(
SELECT TOP 1 MAX(PublishedDate)
FROM Tmax
WHERE IsActive=1
)