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Student(S#(ѧºÅ),Sname(ÐÕÃû),Sage(ÄêÁä),Ssex(ÐÔ±ð)) ѧÉú±í
Course(C#(¿Î³Ì±àºÅ),Cname(¿Î³ÌÃû³Æ),T#(ÀÏʦ±àºÅ)) ¿Î³Ì±í
SC(S#(ѧºÅ),C#(¿Î³Ì±àºÅ),score(·ÖÊý)) ³É¼¨±í
Teacher(T#(ÀÏʦ±àºÅ),TnameSname(ÐÕÃû)) ½Ìʦ±í
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select a.S# from (select s#,score from SC where C#='001') a,(select s#,score
from SC where C#='002') b
where a.score>b.score and a.s#=b.s#;
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select S#,avg(score)
from sc
group by S# having avg(score) >60;
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select Student.S#,Student.Sname,count(SC.C#),sum(score)
from Student left Outer join SC on Student.S#=SC.S#
group by Student.S#,Sname
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select count(distinct(Tname))
from Teacher
where Tname like 'Àî%';
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select Student.S#,Student.Sname
from Student
where S# not in (select distinct( SC.S#) from SC,Course,Teacher where SC.C#=Course.C# and Teacher.T#=Course.T# and Teacher.Tname='Ҷƽ');
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select Student.S#,Student.Sname from Student,SC where Student.S#=SC.S# and SC.C#='001'and exists( Select * from SC as SC_2 where SC_2.S#=SC.S# and SC_2.C#='002');
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select S#,Sname
from Student
where S# in (select S# from SC ,Course ,Teacher where SC.C#=Course.C# and Teacher.T#=Course.T# and Teacher.Tname='Ҷƽ' group by S# having count(SC.C#)=(select count(C#) from Course,Teacher where Teacher.T#=Course.T# and Tname='Ҷƽ'));
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SELECT NAME
from SALESREPS
WHERE HIRE_DATE<'01-JAN-88'
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SELECT CITY,SALES,TAGET
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