How to number SQL results sequentially? Given following query - 

SELECT name, age FROM students WHERE age &gt; 22


The result is - 

name    age
----   ---
Kshitiz 23
Steve   22
Paul    24


How can I number the results sequentially? Like so - 

serial  name    age
------  ----    ---
   1    Kshitiz 23
   2    Steve   22
   3    Paul    24


Please note that using surrogate key is not a solution. Because the surrogate id for record Kshitiz might be 9. I want whatever results are returned from whatever location to be numbered sequentially.
SELECT @a := @a + 1 serial, name, age
FROM students, (SELECT @a :=0) AS dummy
WHERE age &gt; 22;


This works for MySQL. I was modifying from this example.