错误 #2820
慢sql
状态: | 保留 | 开始日期: | 2019-02-21 | |
---|---|---|---|---|
优先级: | 高 | 计划完成日期: | ||
指派给: | 王 天淼 | % 完成: | 0% | |
类别: | - | |||
目标版本: | - | |||
模块: | 后台管理 |
描述
正式系统执行时间为51秒,考虑使用中间表
select * from (
SELECT MAX as checkpoint,us.real_name,role.nick_name from
train_bc_ranking_log log
LEFT JOIN sys_user us on log.user_id=us.id
LEFT JOIN train_role_info role ON role.user_id = log.user_id
LEFT JOIN school_student student on log.user_id=student.user_id
LEFT JOIN school_relation rel on rel.student_id=student.id
LEFT JOIN school_info info on info.id=rel.school_id
WHERE us.id is not null AND us.status = 1 AND student.name is not null
GROUP BY log.user_id
ORDER BY checkpoint desc
) t limit 0,10