PERCENT_RANK

Returns the relative rank of a given value within a set of values. The resulting value falls between 0 and 1, inclusive. Please note that the first row in any set has a PERCENT_RANK of 0.

Analyze Syntax

func.percent_rank().over(partition_by=[<columns>], order_by=[<columns>])

Analyze Examples

table.name, table.score, table.grade, func.percent_rank().over(partition_by=[table.grade], order_by=table.score).alias('percent_rank')

name    |score|grade|percent_rank      |
--------+-----+-----+------------------+
Smith   |   81|A    |               0.0|
Davies  |   84|A    |0.3333333333333333|
Evans   |   87|A    |0.6666666666666666|
Johnson |  100|A    |               1.0|
Taylor  |   62|B    |               0.0|
Brown   |   62|B    |               0.0|
Wilson  |   72|B    |0.6666666666666666|
Thomas  |   72|B    |0.6666666666666666|
Jones   |   55|C    |               0.0|
Williams|   55|C    |               0.0|

SQL Syntax

PERCENT_RANK() OVER (
	PARTITION BY expr, ...
	ORDER BY expr [ASC | DESC], ...
)

SQL Examples

This example retrieves the students' names, scores, grades, and the percentile ranks (percent_rank) within each grade using the PERCENT_RANK() window function.

CREATE TABLE students (
    name VARCHAR(20),
    score INT NOT NULL,
    grade CHAR(1) NOT NULL
);

INSERT INTO students (name, score, grade)
VALUES
    ('Smith', 81, 'A'),
    ('Jones', 55, 'C'),
    ('Williams', 55, 'C'),
    ('Taylor', 62, 'B'),
    ('Brown', 62, 'B'),
    ('Davies', 84, 'A'),
    ('Evans', 87, 'A'),
    ('Wilson', 72, 'B'),
    ('Thomas', 72, 'B'),
    ('Johnson', 100, 'A');

SELECT
    name,
    score,
    grade,
    PERCENT_RANK() OVER (PARTITION BY grade ORDER BY score) AS percent_rank
FROM
    students;

name    |score|grade|percent_rank      |
--------+-----+-----+------------------+
Smith   |   81|A    |               0.0|
Davies  |   84|A    |0.3333333333333333|
Evans   |   87|A    |0.6666666666666666|
Johnson |  100|A    |               1.0|
Taylor  |   62|B    |               0.0|
Brown   |   62|B    |               0.0|
Wilson  |   72|B    |0.6666666666666666|
Thomas  |   72|B    |0.6666666666666666|
Jones   |   55|C    |               0.0|
Williams|   55|C    |               0.0|

Last modified June 11, 2024 at 7:47 PM EST: adding window functions (6bcb2f2)