题解 | 下单最多的商品
下单最多的商品
https://www.nowcoder.com/practice/d7c93e3a3d5b4087896539121d32d367
select product_id, count(distinct trace_id) as cnt from user_client_log where step = 'order' group by product_id order by count(distinct trace_id) desc, product_id asc limit 1