SQL Server 2012，選擇兩個最大記錄，然後加入

Question

我試圖進行使用常見的ScheduledObjectID字段的多表連接。我想從基於最大RunID和UserDueDate的表中選擇多個記錄。任何幫助將不勝感激。

的樣本數據：

ScheduledObjectID RunID UserDueDate 
------------------------------------------------- 
123    1  2017-07-16 14:26:56.263 
123    2  2017-05-16 14:26:56.250 
123    3  2017-05-16 14:26:56.233 
456    9  2017-05-16 14:26:56.217 
456    10  2017-05-16 14:26:56.200 
456    11  2017-10-07 10:19:33.873 

希望加入數據

ScheduledObjectID RunID UserDueDate 
------------------------------------------------- 
123    3  2017-05-16 14:26:56.233 
456    11  2017-10-07 10:19:33.873 

Answer 1

無需加盟，您可以用頂部1與領帶

demo here

select top 1 with ties ScheduledObjectID, RunID, UserDueDate 
from 
#tmp 
order by 
row_number() over (Partition by ScheduledObjectID order by runid desc) 

按照評論這應該工作：

select * from t1 join 
(select ScheduledObjectID,max(runid) as runid,max(userduedate) as userduedate 
from t2 

組由ScheduledObjectID ）上t1.somecol1 = t2.somecol T2