题解 | 电商平台需要对商家的销售业绩、退款情况和客户满意度进行综合评估

with t1 as (
    select a.merchant_id, merchant_name,
    sum(sale_amount) as total_sales_amount
    from merchants_underline a join sales_underline b on a.merchant_id=b.merchant_id
    group by a.merchant_id, merchant_name
), t2 as (
    select merchant_id, sum(refund_amount) as total_refund_amount
    from refunds_underline
    group by merchant_id
), t3 as (
    select merchant_id, round(avg(satisfaction_score), 2) as average_satisfaction_score
    from satisfaction_underline
    group by merchant_id
)
select t1.merchant_id, merchant_name, total_sales_amount, total_refund_amount, average_satisfaction_score
from t1
join t2 on t1.merchant_id=t2.merchant_id
join t3 on t1.merchant_id=t3.merchant_id
order by t1.merchant_id