题解 | 查询出每个品牌在特定时间段内的退货率以及平均客户满意度评分

select
    b.brand_id,
    b.brand_name,
    round(sum(s.return_status)/count(s.order_id),2) as return_rate_July_2024,
    round(avg(f.customer_satisfaction_score),2) as average_customer_satisfaction_score    
from brand_info b 
left join sales_orders s on b.brand_id=s.brand_id
left join customer_feedback f on s.order_id=f.order_id
where s.order_date between '2024-07-01' and '2024-07-31'
group by
    b.brand_id,b.brand_name
order by 
    b.brand_id