题解 | 获取指定客户每月的消费额

select
    DATE_FORMAT(tr.t_time, '%Y-%m') as time,
    sum(tr.t_amount) as total
from
    trade tr
join
    customer c on tr.t_cus = c.c_id
where
    c.c_name = "Tom"
    and YEAR(tr.t_time) = 2023
    and tr.t_type = 1
group by
    DATE_FORMAT(tr.t_time, '%Y-%m')
order by
    time asc

• # 粗暴解题
• 格式注意
• DATE_FORMAT(tr.t_time, '%Y-%m')
• asc 升序