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select i.sid,i.sname,i.birthday,i.schooltime,i.sphone,c.classname,a.assnname,sum(decode(subject,'ÓïÎÄ',s.score,0)) as chin,
sum(decode(subject,'Êýѧ',s.score,0)) as math,
sum(decode(subject,'Ó¢Óï',s.score,0)) as eng from student_info i
left join student_expand e on i.sid = e.sid left join student_class c on
c.classid = e.classid left join student_assn a on a.assnid = e.assnid left join student_score s on s.sid = i.sid
group by i.sid,i.sname,i.birthday,i.schooltime,i.sphone,c.classname,a.assnname;
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decode(subject,'Êýѧ',s.score,0) Ó÷¨:Èç¹ûsubject»áµÈÓÚÊýѧ ,Ôò×îºóÖµµÈÓÚ s.score ·ñÔòÖµµÈÓÚ: 0
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>create user username identified by username;
>grant create tablespace, resource ,connect to username;
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>select username from all_users;
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