How to determine natural numbers

CREATE TABLE Nothing (God XML );



- zero

SELECT count (*) AS X FROM

Nothing;



- one

SELECT count (*) AS X FROM

( SELECT count (*) AS X FROM Nothing) X;

')

- two

SELECT count (*) AS X FROM

( SELECT count (*) AS X FROM Nothing

UNION

SELECT count (*) AS X FROM ( SELECT count (*) AS X FROM Nothing) X) X;



- and so on ...