Mysql - 在同一個查詢中獲取不同時間間隔的數據

Question

我的下面的查詢給了我過去2小時播放的頂級視頻的結果，但是我的要求是也獲得過去4小時的頂級視頻到過去2小時，例如如果通過這個查詢，我從01:00 PM到03:00 PM獲取數據，我還希望從09:00 AM到01:00 PM的數據。我可以在一個查詢中以高效的方式做到這一點。

查詢：

select SQL_CACHE channel,SUBSTRING_INDEX(GROUP_CONCAT(video_id ORDER BY plays DESC),',', 40) AS video_ids,now() as datetime from 
(SELECT channel,video_id,count(video_id) as plays FROM `tbl` 
WHERE `datetime_col` > DATE_SUB(now(), INTERVAL 2 HOUR) 
and channel != 0 
and cat_id != 8 
group by channel,video_id 
order by channel,plays DESC)x 
group by channel; 

在此先感謝。

Answer 1

您可以使用與UNION相同的查詢對結果進行分組。此外，您可以使用BETWEEN來定義間隔，例如

select SQL_CACHE channel,SUBSTRING_INDEX(GROUP_CONCAT(video_id ORDER BY plays DESC),',', 40) AS video_ids,now() as datetime from 
(SELECT channel,video_id,count(video_id) as plays FROM `tbl` 
WHERE `datetime_col` BETWEEN DATE_SUB(now(), INTERVAL 2 HOUR) AND NOW() 
and channel != 0 
and cat_id != 8 
group by channel,video_id 
order by channel,plays DESC)x 
group by channel 

UNION 

select SQL_CACHE channel,SUBSTRING_INDEX(GROUP_CONCAT(video_id ORDER BY plays DESC),',', 40) AS video_ids,DATE_SUB(now(), INTERVAL 2 HOUR) as datetime from 
(SELECT channel,video_id,count(video_id) as plays FROM `tbl` 
WHERE `datetime_col` BETWEEN DATE_SUB(now(), INTERVAL 4 HOUR) AND DATE_SUB(now(), INTERVAL 2 HOUR) 
and channel != 0 
and cat_id != 8 
group by channel,video_id 
order by channel,plays DESC)x 
group by channel;