Query needed for this sol.

[abhishek jain]

Hi all,
I need a query for the fol. sol.
In a table i have 100s of rows with six categories like A,B,C,D,E,F which is
marked with a column like
Table
ID Category
1   A
2   A
3  B
4   B
5  B
6 C
7 C

and so on 100 ids for each of six categories , i want to delete all but 10
ids of each category, i wanted to know how to do so,

Pl. help
Thanks,
Abhishek jain