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CREATE TABLE Student
(Sno CHAR(9) PRIMARY KEY,
Sname CHAR(20) UNIQUE,
Ssex CHAR(2),
Sage SMALLINT,
Sdept CHAR(15));
CREATE TABLE Course
(Cno CHAR(4) PRIMARY KEY ,
Cname CHAR(40) ,
Cpno CHAR(4) ,
Ccredit SMALLINT ,
FOREIGN KEY (Cpno) REFERENCES Course(Cno));
CREATE TABLE SC
(Sno CHAR(9) ,
Cno CHAR(4) ,
Grade SMALLINT ,
PRIMARY KEY(Sno, Cno) ,
FOREIGN KEY (Sno) REFERENCES Student(Sno),
FOREIGN KEY (Cno) REFERENCES Course(Cno));
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select top 1 id,sum(score) from TB
group by id
order by sum(score)
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select top 1 s.sno,sum(Ccredit) as g
from s join sc on s.sno=sc.sno
join course c on sc.cn
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