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MYSQL count standard quantum query how to change left join, I believe that many inexperienced people do not know what to do, so this paper summarizes the causes of the problem and solutions, through this article I hope you can solve this problem.

SELECThomepageId,userId,homepagesummary,totalviews,totalleadpercents,totalappointments,homepagestatus,linkphone,imagepath,createtime,updatetime,recommendtime,sortcode,designerimagepath,isrecommend, (SELECTcount (*) FROMhomepagexxxrelationWHEREhomepageid = h.homepageidAND groundingstatus = 0) AS totalxxx, (SELECTcount (*) FROMhomepagexxxrelationWHEREhomepageid = h.homepageidAND groundingstatus = 0AND Createtime > = DATE_SUB (sysdate (), INTERVAL 7 DAY)) AS weektotalxxxFROMdesignerhomepage hWHERE1 = 1 and isrecommend=1 order by weektotalxxx DESC,homepageid DESC Optimized: SELECTh.homepageId,h.userId,h.homepagesummary,h.totalviews,h.totalleadpercents,h.totalappointments,h.homepagestatus,h.linkphone,h.imagepath,h.createtime,h.updatetime,h.recommendtime,h.sortcode,h.designerimagepath,h.isrecommend, ifnull (h3.cnt2 DAY 0) AS totalscheme,ifnull (h3.cnt1 DAY 0) AS weektotalxxxFROMdesignerhomepage hLEFT JOIN (SELECTHomepageid,sum (case when HP.Createtime > = DATE_SUB (sysdate (), INTERVAL 7 DAY) then 1 else 0 end) cnt1 Count (*) cnt2FROMhomepagexxxrelation hpWHEREHP.groundingstatus = 0GROUP BYHomepageid) h3 ON h3.homepageid = h.homepageidWHERE1 = 1and isrecommend=1ORDER BYweektotalxxx DESC,homepageid DESC After reading the above, have you mastered the method of how to change left join in MYSQL count scalar quantum query? If you want to learn more skills or want to know more about it, you are welcome to follow the industry information channel, thank you for reading!

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