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PERCENT_RANK (Transact-SQL)

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric

Calculates the relative rank of a row within a group of rows in SQL Server. Use PERCENT_RANK to evaluate the relative standing of a value within a query result set or partition. PERCENT_RANK is similar to the CUME_DIST function.

Syntax

PERCENT_RANK( )
    OVER ( [ partition_by_clause ] order_by_clause )

Arguments

OVER ( [ partition_by_clause ] order_by_clause )

The first parameter, partition_by_clause, divides the result set produced by the FROM clause into partitions to which the function is applied. If not specified, the function treats all rows of the query result set as a single group. The second parameter, order_by_clause, determines the logical order in which the operation is performed. order_by_clause is required. The <rows or range clause> of the OVER syntax can't be specified in a PERCENT_RANK function. For more information, see SELECT - OVER Clause.

Return types

float(53)

Remarks

The range of values returned by PERCENT_RANK is greater than 0 and less than or equal to 1. The first row in any set has a PERCENT_RANK of 0. NULL values are included by default and are treated as the lowest possible values.

PERCENT_RANK is nondeterministic. For more information, see Deterministic and nondeterministic functions.

Examples

The Transact-SQL code samples in this article use the AdventureWorks2022 or AdventureWorksDW2022 sample database, which you can download from the Microsoft SQL Server Samples and Community Projects home page.

The following example uses the CUME_DIST function to compute the salary percentile for each employee within a given department. The value returned by the CUME_DIST function represents the percent of employees that have a salary less than or equal to the current employee in the same department. The PERCENT_RANK function computes the rank of the employee's salary within a department as a percentage. The PARTITION BY clause is specified to partition the rows in the result set by department. The ORDER BY clause in the OVER clause orders the rows in each partition. The ORDER BY clause in the SELECT statement sorts the rows in the whole result set.

USE AdventureWorks2022;
GO

SELECT Department,
    LastName,
    Rate,
    CUME_DIST() OVER (PARTITION BY Department ORDER BY Rate) AS CumeDist,
    PERCENT_RANK() OVER (PARTITION BY Department ORDER BY Rate) AS PctRank
FROM HumanResources.vEmployeeDepartmentHistory AS edh
INNER JOIN HumanResources.EmployeePayHistory AS e
    ON e.BusinessEntityID = edh.BusinessEntityID
WHERE Department IN (N'Information Services', N'Document Control')
ORDER BY Department, Rate DESC;

Here's the result set.

Department             LastName               Rate              CumeDist           PctRank
---------------------- ---------------------- ----------------- ------------------ ------------------
Document Control       Arifin                 17.7885           1                  1
Document Control       Norred                 16.8269           0.8                0.5
Document Control       Kharatishvili          16.8269           0.8                0.5
Document Control       Chai                   10.25             0.4                0
Document Control       Berge                  10.25             0.4                0
Information Services   Trenary                50.4808           1                  1
Information Services   Conroy                 39.6635           0.9                0.888888888888889
Information Services   Ajenstat               38.4615           0.8                0.666666666666667
Information Services   Wilson                 38.4615           0.8                0.666666666666667
Information Services   Sharma                 32.4519           0.6                0.444444444444444
Information Services   Connelly               32.4519           0.6                0.444444444444444
Information Services   Berg                   27.4038           0.4                0
Information Services   Meyyappan              27.4038           0.4                0
Information Services   Bacon                  27.4038           0.4                0
Information Services   Bueno                  27.4038           0.4                0