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ROW_NUMBER (Transact-SQL)

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric

Numbers the output of a result set. More specifically, returns the sequential number of a row within a partition of a result set, starting at 1 for the first row in each partition.

ROW_NUMBER and RANK are similar. ROW_NUMBER numbers all rows sequentially (for example 1, 2, 3, 4, 5). RANK provides the same numeric value for ties (for example 1, 2, 2, 4, 5).

Note

ROW_NUMBER is a temporary value calculated when the query is run. To persist numbers in a table, see IDENTITY Property and SEQUENCE.

Transact-SQL syntax conventions

Syntax

ROW_NUMBER ( )   
    OVER ( [ PARTITION BY value_expression , ... [ n ] ] order_by_clause )  

Arguments

PARTITION BY value_expression
Divides the result set produced by the FROM clause into partitions to which the ROW_NUMBER function is applied. value_expression specifies the column by which the result set is partitioned. If PARTITION BY is not specified, the function treats all rows of the query result set as a single group. For more information, see OVER Clause (Transact-SQL).

order_by_clause
The ORDER BY clause determines the sequence in which the rows are assigned their unique ROW_NUMBER within a specified partition. It is required. For more information, see OVER Clause (Transact-SQL).

Return Types

bigint

General Remarks

There is no guarantee that the rows returned by a query using ROW_NUMBER() will be ordered exactly the same with each execution unless the following conditions are true.

  • Values of the partitioned column are unique.

  • Values of the ORDER BY columns are unique.

  • Combinations of values of the partition column and ORDER BY columns are unique.

If the ORDER BY columns are not unique within the results, consider using RANK() or DENSE_RANK().

ROW_NUMBER() is nondeterministic. For more information, see Deterministic and Nondeterministic Functions.

Examples

A. Simple examples

The following query returns the four system tables in alphabetic order.

SELECT 
  name, recovery_model_desc
FROM sys.databases 
WHERE database_id < 5
ORDER BY name ASC;

Here's the result set.

name recovery_model_desc
master SIMPLE
model FULL
msdb SIMPLE
tempdb SIMPLE

To add a row number column in front of each row, add a column with the ROW_NUMBER function, in this case named Row#. You must move the ORDER BY clause up to the OVER clause.

SELECT 
  ROW_NUMBER() OVER(ORDER BY name ASC) AS Row#,
  name, recovery_model_desc
FROM sys.databases 
WHERE database_id < 5;

Here's the result set.

Row# name recovery_model_desc
1 master SIMPLE
2 model FULL
3 msdb SIMPLE
4 tempdb SIMPLE

The PARTITION BY clause on the recovery_model_desc column, restarts the numbering when the recovery_model_desc value changes.

SELECT 
  ROW_NUMBER() OVER(PARTITION BY recovery_model_desc ORDER BY name ASC) 
    AS Row#,
  name, recovery_model_desc
FROM sys.databases WHERE database_id < 5;

Here's the result set.

Row# name recovery_model_desc
1 model FULL
1 master SIMPLE
2 msdb SIMPLE
3 tempdb SIMPLE

B. Returning the row number for salespeople

The following example calculates a row number for the salespeople in Adventure Works Cycles based on their year-to-date sales ranking.

USE AdventureWorks2022;   
GO  
SELECT ROW_NUMBER() OVER(ORDER BY SalesYTD DESC) AS Row,   
    FirstName, LastName, ROUND(SalesYTD,2,1) AS "Sales YTD"   
FROM Sales.vSalesPerson  
WHERE TerritoryName IS NOT NULL AND SalesYTD <> 0;  

Here's the result set.

  
Row FirstName    LastName               SalesYTD  
--- -----------  ---------------------- -----------------  
1   Linda        Mitchell               4251368.54  
2   Jae          Pak                    4116871.22  
3   Michael      Blythe                 3763178.17  
4   Jillian      Carson                 3189418.36  
5   Ranjit       Varkey Chudukatil      3121616.32  
6   José         Saraiva                2604540.71  
7   Shu          Ito                    2458535.61  
8   Tsvi         Reiter                 2315185.61  
9   Rachel       Valdez                 1827066.71  
10  Tete         Mensa-Annan            1576562.19  
11  David        Campbell               1573012.93  
12  Garrett      Vargas                 1453719.46  
13  Lynn         Tsoflias               1421810.92  
14  Pamela       Ansman-Wolfe           1352577.13  

C. Returning a subset of rows

The following example calculates row numbers for all rows in the SalesOrderHeader table in the order of the OrderDate and returns only rows 50 to 60 inclusive.

USE AdventureWorks2022;  
GO  
WITH OrderedOrders AS  
(  
    SELECT SalesOrderID, OrderDate,  
    ROW_NUMBER() OVER (ORDER BY OrderDate) AS RowNumber  
    FROM Sales.SalesOrderHeader   
)   
SELECT SalesOrderID, OrderDate, RowNumber    
FROM OrderedOrders   
WHERE RowNumber BETWEEN 50 AND 60;  

D. Using ROW_NUMBER() with PARTITION

The following example uses the PARTITION BY argument to partition the query result set by the column TerritoryName. The ORDER BY clause specified in the OVER clause orders the rows in each partition by the column SalesYTD. The ORDER BY clause in the SELECT statement orders the entire query result set by TerritoryName.

USE AdventureWorks2022;  
GO  
SELECT FirstName, LastName, TerritoryName, ROUND(SalesYTD,2,1) AS SalesYTD,  
ROW_NUMBER() OVER(PARTITION BY TerritoryName ORDER BY SalesYTD DESC) 
  AS Row  
FROM Sales.vSalesPerson  
WHERE TerritoryName IS NOT NULL AND SalesYTD <> 0  
ORDER BY TerritoryName;  

Here's the result set.

  
FirstName  LastName             TerritoryName        SalesYTD      Row  
---------  -------------------- ------------------   ------------  ---  
Lynn       Tsoflias             Australia            1421810.92    1  
José       Saraiva              Canada               2604540.71    1  
Garrett    Vargas               Canada               1453719.46    2  
Jillian    Carson               Central              3189418.36    1  
Ranjit     Varkey Chudukatil    France               3121616.32    1  
Rachel     Valdez               Germany              1827066.71    1  
Michael    Blythe               Northeast            3763178.17    1  
Tete       Mensa-Annan          Northwest            1576562.19    1  
David      Campbell             Northwest            1573012.93    2  
Pamela     Ansman-Wolfe         Northwest            1352577.13    3  
Tsvi       Reiter               Southeast            2315185.61    1  
Linda      Mitchell             Southwest            4251368.54    1  
Shu        Ito                  Southwest            2458535.61    2  
Jae        Pak                  United Kingdom       4116871.22    1  

Examples: Azure Synapse Analytics and Analytics Platform System (PDW)

E. Returning the row number for salespeople

The following example returns the ROW_NUMBER for sales representatives based on their assigned sales quota.

-- Uses AdventureWorks  
  
SELECT ROW_NUMBER() OVER(ORDER BY SUM(SalesAmountQuota) DESC) 
    AS RowNumber,  
    FirstName, LastName,   
    CONVERT(varchar(13), SUM(SalesAmountQuota),1) AS SalesQuota   
FROM dbo.DimEmployee AS e  
INNER JOIN dbo.FactSalesQuota AS sq  
    ON e.EmployeeKey = sq.EmployeeKey  
WHERE e.SalesPersonFlag = 1  
GROUP BY LastName, FirstName;  

Here is a partial result set.


RowNumber  FirstName  LastName            SalesQuota  
---------  ---------  ------------------  -------------  
1          Jillian    Carson              12,198,000.00  
2          Linda      Mitchell            11,786,000.00  
3          Michael    Blythe              11,162,000.00  
4          Jae        Pak                 10,514,000.00  

F. Using ROW_NUMBER() with PARTITION

The following example shows using the ROW_NUMBER function with the PARTITION BY argument. This causes the ROW_NUMBER function to number the rows in each partition.

-- Uses AdventureWorks  
  
SELECT ROW_NUMBER() OVER(PARTITION BY SalesTerritoryKey 
        ORDER BY SUM(SalesAmountQuota) DESC) AS RowNumber,  
    LastName, SalesTerritoryKey AS Territory,  
    CONVERT(varchar(13), SUM(SalesAmountQuota),1) AS SalesQuota   
FROM dbo.DimEmployee AS e  
INNER JOIN dbo.FactSalesQuota AS sq  
    ON e.EmployeeKey = sq.EmployeeKey  
WHERE e.SalesPersonFlag = 1  
GROUP BY LastName, FirstName, SalesTerritoryKey;  

Here is a partial result set.

 
RowNumber  LastName            Territory  SalesQuota  
---------  ------------------  ---------  -------------  
1          Campbell            1           4,025,000.00  
2          Ansman-Wolfe        1           3,551,000.00  
3          Mensa-Annan         1           2,275,000.00  
1          Blythe              2          11,162,000.00  
1          Carson              3          12,198,000.00  
1          Mitchell            4          11,786,000.00  
2          Ito                 4           7,804,000.00  

See Also

RANK (Transact-SQL)
DENSE_RANK (Transact-SQL)
NTILE (Transact-SQL)