PERCENT_RANK

Description

PERCENT_RANK() is a window function that calculates the relative rank of a row within a partition or result set, returning values from 0.0 to 1.0. For a given row, it is calculated as: (rank - 1) / (total_rows - 1), where rank is the current row's rank and total_rows is the total number of rows in the partition.

Syntax

PERCENT_RANK()

Return Value

Returns a DOUBLE value ranging from 0.0 to 1.0:

• Always returns 0 for the first row in the partition
• Always returns 1 for the last row in the partition
• Returns the same percentage rank for identical values

Examples

CREATE TABLE test_percent_rank (
    productLine VARCHAR,
    orderYear INT,
    orderValue DOUBLE,
    percentile_rank DOUBLE
) ENGINE=OLAP
DISTRIBUTED BY HASH(`orderYear`) BUCKETS 4
PROPERTIES (
"replication_allocation" = "tag.location.default: 1"
);

INSERT INTO test_percent_rank (productLine, orderYear, orderValue, percentile_rank) VALUES
('Motorcycles', 2003, 2440.50, 0.00),
('Trains', 2003, 2770.95, 0.17),
('Trucks and Buses', 2003, 3284.28, 0.33),
('Vintage Cars', 2003, 4080.00, 0.50),
('Planes', 2003, 4825.44, 0.67),
('Ships', 2003, 5072.71, 0.83),
('Classic Cars', 2003, 5571.80, 1.00),
('Motorcycles', 2004, 2598.77, 0.00),
('Vintage Cars', 2004, 2819.28, 0.17),
('Planes', 2004, 2857.35, 0.33),
('Ships', 2004, 4301.15, 0.50),
('Trucks and Buses', 2004, 4615.64, 0.67),
('Trains', 2004, 4646.88, 0.83),
('Classic Cars', 2004, 8124.98, 1.00),
('Ships', 2005, 1603.20, 0.00),
('Motorcycles', 2005, 3774.00, 0.17),
('Planes', 2005, 4018.00, 0.50),
('Vintage Cars', 2005, 5346.50, 0.67),
('Classic Cars', 2005, 5971.35, 0.83),
('Trucks and Buses', 2005, 6295.03, 1.00);

SELECT
    productLine,
    orderYear,
    orderValue,
    ROUND(
    PERCENT_RANK()
    OVER (
        PARTITION BY orderYear
        ORDER BY orderValue
    ),2) percentile_rank
FROM
    test_percent_rank
ORDER BY
    orderYear;

+------------------+-----------+------------+-----------------+
| productLine      | orderYear | orderValue | percentile_rank |
+------------------+-----------+------------+-----------------+
| Motorcycles      |      2003 |     2440.5 |               0 |
| Trains           |      2003 |    2770.95 |            0.17 |
| Trucks and Buses |      2003 |    3284.28 |            0.33 |
| Vintage Cars     |      2003 |       4080 |             0.5 |
| Planes           |      2003 |    4825.44 |            0.67 |
| Ships            |      2003 |    5072.71 |            0.83 |
| Classic Cars     |      2003 |     5571.8 |               1 |
| Motorcycles      |      2004 |    2598.77 |               0 |
| Vintage Cars     |      2004 |    2819.28 |            0.17 |
| Planes           |      2004 |    2857.35 |            0.33 |
| Ships            |      2004 |    4301.15 |             0.5 |
| Trucks and Buses |      2004 |    4615.64 |            0.67 |
| Trains           |      2004 |    4646.88 |            0.83 |
| Classic Cars     |      2004 |    8124.98 |               1 |
| Ships            |      2005 |     1603.2 |               0 |
| Motorcycles      |      2005 |       3774 |             0.2 |
| Planes           |      2005 |       4018 |             0.4 |
| Vintage Cars     |      2005 |     5346.5 |             0.6 |
| Classic Cars     |      2005 |    5971.35 |             0.8 |
| Trucks and Buses |      2005 |    6295.03 |               1 |
+------------------+-----------+------------+-----------------+