题解 | 短视频直播间晚上11-12点之间各直播间的在线人数

select a.room_id, room_name, count(*) 'user_count'
from(
    select distinct room_id,user_id
    from user_view_tb u 
    where out_time >= "23:00:00" and out_time <= "24:00:00"
)a
join room_info_tb r
on a.room_id = r.room_id
group by a.room_id,room_name
order by user_count desc;

需要注意用户会多次进入直播间，所以需要使用select distinct room_id,user_id,from user_view_tb u where out_time >= "23:00:00" and out_time <= "24:00:00"