with a as 
(
	select 
	t1.product_id product_id
	,count(*) count
	from user_client_log t1
	join product_info t2
	on t1.product_id = t2.product_id
	where t1.step = 'order'
	group by 1
) 
select
product_id
,count cnt 
from a 
where count = (select max(count) from a)
order by 1