题解 | #统计2021年10月每个退货率不大于0.5的商品

select 
    product_id,
    if(count(id) = 0,0,round(sum(if_click)/count(id),3)) ctr,
    if(sum(if_click) = 0,0,round(sum(if_cart)/sum(if_click),3)) as cart_rate,
    if(sum(if_cart) = 0,0,round(sum(if_payment)/sum(if_cart),3)) as payment_rate,
    if(sum(if_payment) = 0,0,round(sum(if_refund)/sum(if_payment),3)) as refund_rate
from 
    tb_user_event
where 
    date_format(event_time, '%Y-%m') = '2021-10'
group by 
    product_id
having 
    if(sum(if_payment) = 0,0,round(sum(if_refund)/sum(if_payment),3)) <= 0.5
order by 
    product_id