SELECT mt.id FROM maps_tiles mt
WHERE mt.map_id=1
            AND (mt.x BETWEEN 10 AND 16)
            AND (mt.y BETWEEN 17 AND 23)
AND mt.id NOT IN
(SELECT mt.id
            FROM users_tiles ut RIGHT JOIN maps_tiles mt ON ut.tile_id=mt.id
            WHERE mt.map_id=1 AND (ut.user_id=1)
            AND (mt.x BETWEEN 10 AND 16)
            AND (mt.y BETWEEN 17 AND 23))