一個挺長的多表聯查SQL語句

 select *  from AP_Detail 
left join (select UserID,u_cname,(select G_CName from sys_Group where GroupID =sys_User .U_GroupID) as G_CName from sys_User) as userinfo(userid,username,gropname)
on AP_Detail .D_UserID=userinfo.userid
left join (select AP_DetailID,userinfo.duserid ,userinfo .dusername,userinfo .dgropname   from AP_Detail 
left join (select UserID,u_cname,(select G_CName from sys_Group where GroupID =sys_User .U_GroupID) as G_CName from sys_User) as userinfo(duserid,dusername,dgropname)
on AP_Detail .D_DUserID=userinfo.duserid) as duserinfo(adID,duserid,dusername,dgropname) on AP_Detail .AP_DetailID =duserinfo.adID where D_PrimaryID =2

 

這個是同事寫的多表聯查的SQL語句，感覺太長了，應該可以再簡化一下。先記下來，日後研究。