ROW_NUMBER

Returns a unique row number for each row within the requested window.

For more information on usage, please refer to Window Functions.

Syntax

ROW_NUMBER() OVER ([PARTITION BY <partition_by>] ORDER BY <order_by> [ASC|DESC] )

Parameter	Description	Supported input types
`<partition_by>`	The expression used for the `PARTITION BY` clause.	Any
`<order_by>`	The expression used in the `ORDER BY` clause. This parameter determines what value will be used for `ROW_NUMBER`.	Any

INTEGER

In this example below, players in each game level are assigned a player ID.

SELECT
	nickname,
	level,
	ROW_NUMBER() OVER (PARTITION BY level ORDER BY level ASC ) AS player_id
FROM
	players;

Returns: