题解 | 每天登陆最早的用户的内容喜好

WITH
t1 AS (
SELECT
    DATE(a.log_time) AS log_day,
    a.user_id,
    RANK() OVER (PARTITION BY DATE(a.log_time) ORDER BY a.log_time) AS rk,
    b.hobby
FROM login_tb AS a
INNER JOIN user_action_tb AS b
    ON (a.user_id = b.user_id)
)

SELECT
    log_day,
    user_id,
    hobby
FROM t1
WHERE rk = 1
ORDER BY log_day;