Important

New database features are no longer connected to engine versions; features are now enabled independently during scheduled update windows, and “major” and “minor” releases no longer exist in Helios. Please visit the release notes to view the latest features available in your database clusters.

NTH_VALUE

Syntax

NTH_VALUE ( expression, n ) OVER (
    [PARTITION BY (col | expr), ...]
    [ORDER BY (col | expr), ...]
    [frame_clause]
)

Arguments

expression: Any expression. This may be a column name, the result of another function, or a math operation.
n: An integer or integer expression.

Return Type

The result type of the expression.

Examples

SQL

CREATE TABLE nth_example (a int, b int);

INSERT INTO nth_example VALUES (1, 2), (2, 2), (3, 3), (4, 3);

SQL

SELECT a, NTH_VALUE(a, 2) OVER (ORDER BY a) FROM nth_example;

+------+-----------------------------------+
| a    | NTH_VALUE(a, 2) OVER (ORDER BY a) |
+------+-----------------------------------+
|    1 |                              NULL |
|    2 |                                 2 |
|    3 |                                 2 |
|    4 |                                 2 |
+------+-----------------------------------+

SQL

SELECT a, NTH_VALUE(a, case when a > 2 then 1 else 2 end) OVER
        (ORDER BY a rows between unbounded preceding and unbounded following) as nth_value FROM nth_example;

+------+-----------+
| a    | nth_value |
+------+-----------+
|    1 |         2 |
|    2 |         2 |
|    3 |         1 |
|    4 |         1 |
+------+-----------+