As the other poster said: You don't! Because it's meaningless in a query.
If you need it in a report, you can do it there, but what do you need it for in a query? How do you want your records numbered if you change the 'ORDER BY' from ascending to descending, do you want the record number (or RowId) to change too?
If you insist, you can write a query along this lines (ID is :
SELECT T1.ID,
(Select Count(*) + 1
From MyTable As T2
Where T2.id < T1.id) AS RowID,
T1.Column2, T1.Column3, ...
FROM MyTable AS T1
--WHERE T1.ID < 1000
Hth
PerL