mysql group by 并查出前面几条

mysql group by 并查出前面几条

select a.*,
b.name as bname 
from sk_product a 
left join sk_product_category b 
on a.category_id = b.id  
where 6 > (
    select count(*) 
    from sk_product 
    and order_list > a.order_list 
    ) 
order by a.category_id