Use ROW_NUMBER in a SQL query to add an incrementing value on each row return from a query. Once use for this would be to paginate the results.
--order by last name
SELECT
Users.FirstName
,Users.LastName
,ROW_NUMBER() OVER (ORDER BY Users.LastName) AS RowId
FROM Users
--order by last name DESC
SELECT
Users.FirstName
,Users.LastName
,ROW_NUMBER() OVER (ORDER BY Users.LastName DESC) AS RowId
FROM Users