Question

如何自定义此查询，大约需要30秒才能取出结果，并在＆＃39;视频＆＃39;该表大约有50万，会员和会员中有300万会员。表，是否有任何备用查询或我应该在2个选择查询中中断此查询？

user_id已编入索引 vid_id已编入索引

select a.ref_url , a.source , a.video_name , a.viewers , b.username ,           
c.points from 
members_videos a 
inner join Members b on a.user_id = b.user_id
inner join rankings      c on c.user_id = b.user_id

where a.cat_ids in (123,234,52,234,423,122) not in (110,99)
order by a.vid_id Desc limit 10

Answer 1

有多种因素：

确保members_videos，成员和排名在user_id列上有索引。
打破查询;消除Order By子句。获取临时表中的数据。
从临时表中选择数据并将Order By Clause放在那里。

替代，尝试子查询。

SELECT *
FROM
(
select a.ref_url , a.source , a.video_name , a.viewers , b.username ,           
c.points from 
members_videos a 
inner join Members b on a.user_id = b.user_id
inner join rankings      c on c.user_id = b.user_id
where a.cat_ids in (123,234,52,234,423,122) not in (110,99)
) as T
order by T.vid_id Desc limit 10

MySql：如何减少这个Query的执行时间？

1 个答案: