Row_Number Over Where RowNumber between

Question

I\'m try to select a certain rows from my table using the row_number over. However, the sql will prompt the error msg \"Invalid column name \'ROWNUMBERS\' \". Anyone can cor

Answer 1

Attempting to reference the aliased column in the WHERE clause does not work because of the logical query processing taking place. The WHERE is evaluated before the SELECT clause. Therefore, the column ROWNUMBERS does not exist when WHERE is evaluated.

The correct way to reference the column in this example would be:

SELECT a.*
FROM
    (SELECT ROW_NUMBER() OVER (ORDER BY  Price ASC) AS ROWNUMBERS, * 
    FROM Product) a
WHERE a.ROWNUMBERS BETWEEN @fromCount AND @toCount

For your reference, the order for operations is:

1. FROM
2. WHERE
3. GROUP BY
4. HAVING
5. SELECT
6. ORDER BY