SUM+窗口函数

SELECT 
    u.name AS u_n,
    pn.date,
    SUM(pn.number) OVER(PARTITION BY pn.user_id ORDER BY pn.date) AS ps_num
FROM passing_number pn 
JOIN user u 
    ON pn.user_id = u.id
ORDER BY pn.date, u.name

主要需要注意的地方在于窗口函数内的order by，再加上前面的sum可以起到累加的作用。