Help with ORDER

Hello, I have this script :

    $query.="WHERE u.level >=7 ";
    $query.="AND u.level <=10 ";
    $query.="ORDER BY u.id_level DESC, u.id ASC";

Code (markup):

Because I can't change user's levels I want to order first u.level 9 then u.level 8 then u.level 10 ( instead 7 ) and u.level 7 after 10 how ?

 

Untested:

ORDER BY FIELD(u.level, 9, 8, 10, 7);

Code (markup):