SQLServer单个字段去重的方法

单个字段去重并选出每个分组里面的最大值对应的行：

Row_Number去重：

select * from (select *,row_number()over(partition by Servername order by Check_Date desc) Suquence from AuditItem) s where s.Suquence=1

Croup by写法：

select * from [dbo].[AuditItem] where Check_Date in (select Max(Check_Date) from AuditItem group by servername)