hello, proably quite simple but hope you can help with out too much ridicule.....

I am doing a php/mysql query that returns a column of numbers ordered by their id. At the moment it is sorting it numerically but is sorting it like this:

1
11
12
15
19
2
20
21
22
23
27
3
30
31
4
5
6


but I want 1,2,3,4,5,6,7,8,9,10,11 etc etc

what am I doing wrong?