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Student(S#,Sname,Sage,Ssex) ѧÉú±í
Course(C#,Cname,T#) ¿Î³Ì±í
SC(S#,C#,score) ³É¼¨±í
Teacher(T#,Tname) 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#;
2¡¢²éѯƽ¾ù³É¼¨´óÓÚ60·ÖµÄͬѧµÄѧºÅºÍƽ¾ù³É¼¨£»
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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create table cs
(
txt1 nvarchar(50) null
)
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insert into cs (txt ......
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party(Code,Name,Leader)
Code: Õþµ³´úÂë
Name: Õþµ³ ......
SELECT sysobjects.name,syscolumns.name
from sysobjects,syscolumns
WHERE(sysobjects.id=syscolumns.id)
select col_name(OBJECT_ID(£§staff£§),17)
select name
from syscolumns
where id=object_id(£§ÄãµÄ±íÃû£§); ......
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¡¡¡¡1. /*+ALL_ROWS*/
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