PHP从3000万条记录中检索数据

Question

我在我的moodle网站上使用下面给出的自定义查询并且工作正常但是现在mdl_user_enrollments表中的总记录是3000万，这需要时间将结果返回到我的前端屏幕。请让我知道如何加快速度。

下面的查询

select t1.userid,t2.courseid AS course_id, t1.timestart AS subscription_start, t1.timeend AS subscription_end,t1.timecreated AS timecreated,t1.timemodified AS timemodified, t3.id AS quiz_id,

t3.name AS quiz_name from mdl_user_enrolments t1 

join  mdl_enrol t2 on t1.userid=$user_id and  t1.enrolid = t2.id

join mdl_quiz t3 on t3.course = t2.courseid 

解释输出

Explain mdl_user_enrolments result

Field          Type       Null    Key    Default      Extra     
id           bigint(10)    NO     PRI     NULL         auto_increment 
status       bigint(10)    NO      0    
enrolid      bigint(10)    NO     MUL     NULL  
userid       bigint(10)    NO     MUL     NULL  
timestart    bigint(10)    NO      0 
timeend      bigint(10)    NO   2147483647 
modifierid   bigint(10)    NO      MUL      0   
timecreated  bigint(10)    NO       0   
timemodified bigint(10)    NO       0

分析表mdl_user_enrolments结果

表操作Msg_type Msg_text eLearningDev_v1.mdl_user_enrolments分析状态确定

表格大小mdl_user_enrolments 910 MB

Answer 1

Select t1.userid,t2.courseid AS course_id, t1.timestart AS subscription_start, t1.timeend AS subscription_end,t1.timecreated AS timecreated,t1.timemodified AS timemodified, t3.id AS quiz_id,    
t3.name AS quiz_name from mdl_user_enrolments t1     
LEFT join  mdl_enrol AS  t2 on t1.userid=$user_id and  t1.enrolid = t2.id    
LEFT join mdl_quiz AS  t3 on t3.course = t2.courseid 

希望这对你有用。