题解 | 电商平台需要对商品的销售和评价情况进行综合分析

select 
    p.product_id,
    p.product_name,
    total_quantity,
    average_rating
from products_underline p
join 
    (select product_id,sum(quantity) as total_quantity
    from sales_underline
    group by 1 ) s 
on p.product_id=s.product_id
join 
    (select product_id,round(avg(rating),2) as average_rating
    from reviews_underline 
    group by 1 having average_rating<4) r
on p.product_id=r.product_id
order by 4,1;