mysql按小时统计人数

SELECT 
    DATE_FORMAT(activity_time, '%Y-%m-%d %H:00:00') AS hour,
    COUNT(*) AS user_count
FROM 
    user_activity
GROUP BY 
    hour
ORDER BY 
    hour;

SELECT 
    DATE_FORMAT(activity_time, '%Y-%m-%d %H:00:00') AS hour,
    COUNT(*) AS user_count
FROM 
    user_activity
WHERE 
    activity_time >= '2023-01-01 00:00:00' AND activity_time < '2023-01-02 00:00:00'
GROUP BY 
    hour
ORDER BY 
    hour;

SELECT 
    DATE_FORMAT(activity_time, '%Y-%m-%d %H:00:00') AS hour,
    COUNT(*) AS user_count
FROM 
    user_activity
WHERE 
    activity_time >= '2023-01-01 00:00:00' AND activity_time < '2023-01-02 00:00:00'
GROUP BY 
    hour
ORDER BY 
    hour
LIMIT 10 OFFSET 0;