SQL Row_Number() function in Where Clause

Question

I found one question answered with the Row_Number() function in the where clause. When I tried one query, I was getting the following error:

Answer 1

SELECT  employee_id
FROM    (
        SELECT  employee_id, ROW_NUMBER() OVER (ORDER BY employee_id) AS rn
        FROM    V_EMPLOYEE
        ) q
WHERE   rn > 0
ORDER BY
        Employee_ID

Note that this filter is redundant: ROW_NUMBER() starts from 1 and is always greater than 0.