Select the Highest and Second Highest value in a Group/Category using SQL Server 2005/2008

In one of my previous posts Select the Highest value in a Group/Category using SQL Server 2005/2008, a user asked me if it was possible to find the Highest and the Second Highest Value in a Group/Category. He also wanted to use a Common Table Expression to do so.

Here's the modified query to find the Maximum and Second Maximum value in a Group/Category using a CTE in SQL Server 2005/2008

Sample Data

DECLARE @Student TABLE

(

    StudentId int, SubjectId int, Marks float

)

 

INSERT @Student

SELECT 1,1,8.0 UNION ALL

SELECT 2,1,5.0 UNION ALL

SELECT 3,1,7.0 UNION ALL

SELECT 4,1,9.5 UNION ALL

SELECT 1,2,9.0 UNION ALL

SELECT 2,2,7.0 UNION ALL

SELECT 3,2,4.0 UNION ALL

SELECT 4,2,7.5

Query to fetch the highest and second highest marks in each Subject

;With CTE

AS

(Select Row_number() Over(Partition By SubjectId Order By Marks Desc) as Topp,* From @Student)

Select SubjectId,

  Max(Case When Topp=1 Then Marks End) as '1st Rank',

  Max(Case When Topp=2 Then Marks End) as '2nd Rank'

From CTE

Group By SubjectId

Results

SubjectId    1st Rank    2nd Rank

1              9.5          8

2              9            7.5