题解 | 获取指定客户每月的消费额

with tom_pay as(
select tr.t_time
,date_format(tr.t_time,"%Y-%m") as time
,tr.t_amount
from trade tr 
join customer cu on tr.t_cus = cu.c_id
where cu.c_name="Tom"
and year(tr.t_time)=2023
and tr.t_type=1
)
select time
,round(sum(t_amount),1) as total
from tom_pay
group by time
order by time;