SELECT uid,nick_name,achievement
FROM user_info
WHERE achievement BETWEEN 1200 AND 2500
AND nick_name LIKE '牛客%号'
AND uid IN (
    SELECT uid
    FROM(
        SELECT uid,start_time AS act_time
        FROM exam_record
        UNION ALL
        SELECT uid,submit_time AS act_time
        FROM practice_record
    )temp
    GROUP BY uid
    HAVING DATE_FORMAT(MAX(act_time),'%Y%m') = 202109
)