WINDOW clause

The WINDOW clause allows you to refer to a window by name when you use a ROW_NUMBER function in a SelectExpression.

Syntax

WINDOW windowName AS windowSpecification

In a WINDOW clause, windowName is a SQL92Identifier.

Currently, the only valid windowSpecification is a set of empty parentheses (()), which indicates that the function is evaluated over the entire result set.

Example

SELECT ROW_NUMBER() OVER R, 
    B, 
    SUM(A) 
FROM T5 GROUP BY B WINDOW R AS ()