QUARTER(order_date) = 2直接判断日期为第二季度，本题要理清运行顺序

 select
    pi.product_id,
    pi.product_name,
    sum(ifnull(total_amount,0)) as q2_2024_sales_total # 解决空值问题,
    row_number()over
        (   
            partition by pi.category order by sum(total_amount) desc
        )   as category_rank,
    supplier_name
from
    product_info  as pi
left join 
    order_info    as oi on pi.product_id = oi.product_id 
    and QUARTER(order_date) = 2  # 判断为第二季度
left join
    supplier_info as si on si.product_id = pi.product_id # 连接到pi表解决 supplier_name为 none 问题
group by pi.product_id
order by product_id asc