sql按分组获取多条数据中最新一条

用projectid 作为分组并按id排序，获取最新一条数据。

oracle 、 mysql 用法

 select * from
     ( select row_number() over(partition by ProjectID order by [ID] desc ) as keyId,* from table  )
     as t  where t.keyId = 1

 

sqlserver 用法

SELECT ProjectID,EarnSales FROM table WHERE ID in (  select max(ID) from tablegroup by ProjectID  )