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Ranking Functions (Transact-SQL)

Ranking functions return a ranking value for each row in a partition. Depending on the function that is used, some rows might receive the same value as other rows. Ranking functions are nondeterministic.

Transact-SQL provides the following ranking functions:

RANK

NTILE

DENSE_RANK

ROW_NUMBER

Examples

The following shows the four ranking functions used in the same query. See each ranking function for function specific examples.

USE AdventureWorks;
GO
SELECT c.FirstName, c.LastName
    ,ROW_NUMBER() OVER (ORDER BY a.PostalCode) AS 'Row Number'
    ,RANK() OVER (ORDER BY a.PostalCode) AS 'Rank'
    ,DENSE_RANK() OVER (ORDER BY a.PostalCode) AS 'Dense Rank'
    ,NTILE(4) OVER (ORDER BY a.PostalCode) AS 'Quartile'
    ,s.SalesYTD, a.PostalCode
FROM Sales.SalesPerson s 
    INNER JOIN Person.Contact c 
        ON s.SalesPersonID = c.ContactID
    INNER JOIN Person.Address a 
        ON a.AddressID = c.ContactID
WHERE TerritoryID IS NOT NULL 
    AND SalesYTD <> 0;

Here is the result set.

FirstName

LastName

Row Number

Rank

Dense Rank

Quartile

SalesYTD

PostalCode

Maciej

Dusza

1

1

1

1

4557045

98027

Shelley

Dyck

2

1

1

1

5200475

98027

Linda

Ecoffey

3

1

1

1

3857164

98027

Carla

Eldridge

4

1

1

1

1764939

98027

Carol

Elliott

5

1

1

2

2811013

98027

Jauna

Elson

6

6

2

2

3018725

98055

Michael

Emanuel

7

6

2

2

3189356

98055

Terry

Eminhizer

8

6

2

3

3587378

98055

Gail

Erickson

9

6

2

3

5015682

98055

Mark

Erickson

10

6

2

3

3827950

98055

Martha

Espinoza

11

6

2

4

1931620

98055

Janeth

Esteves

12

6

2

4

2241204

98055

Twanna

Evans

13

6

2

4

1758386

98055