1 CREATE TABLE Depts
 2 (
 3     Dno CHAR(20) PRIMARY KEY,
 4     Dname CHAR(20) NOT NULL
 5 )
 6 INSERT INTO Depts VALUES('D01','自动化')
 7 INSERT INTO Depts VALUES('D02','计算机')
 8 INSERT INTO Depts VALUES('D03','数学')
 9 INSERT INTO Depts VALUES('D04','通信')
10 INSERT INTO Depts VALUES('D05','电子')
11
12 CREATE TABLE Students
13 (
14     Sno  CHAR(20) PRIMARY KEY,
15     Sname CHAR(20) NOT NULL,
16     Ssex CHAR(2),
17     Sage INT,
18     Dno CHAR(20),
19     CONSTRAINT FK_Dno FOREIGN KEY(Dno) REFERENCES Depts
20 )
21 INSERT INTO Students VALUES('S01','王建平','男',21,'D01')
22 INSERT INTO Students VALUES('S02','刘华','女',19,'D01')
23 INSERT INTO Students VALUES('S03','范林军','女',18,'D02')
24 INSERT INTO Students VALUES('S04','李伟','男',19,'D03')
25 INSERT INTO Students VALUES('S05','黄河','男',18,'D03')
26 INSERT INTO Students VALUES('S06','长江','男',20,'D03')
27
28 CREATE TABLE Courses
29 (
30     Cno CHAR(20) PRIMARY KEY,
31     Cname CHAR(20),
32     Pre_Cno CHAR(6),
33     Credits INT
34 )
35 INSERT INTO Courses VALUES('C01','英语',NULL,4)
36 INSERT INTO Courses VALUES('C02','数据结构','C05',2)
37 INSERT INTO Courses VALUES('C03','数据库','C02',2)
38 INSERT INTO Courses VALUES('C04','DB_设计','C03',3)
39 INSERT INTO Courses VALUES('C05','C++',NULL,3)
40 INSERT INTO Courses VALUES('C06','网络原理','C07',3)
41 INSERT INTO Courses VALUES('C07','操作系统','C05',3)
42
43 CREATE TABLE Reports
44 (
45     Sno CHAR(20),
46     Cno CHAR(20),
47     Grade INT,
48     PRIMARY KEY(Sno,Cno),
49     CONSTRAINT Student_Report FOREIGN KEY(Sno) REFERENCES Students,
50     CONSTRAINT Report_Course FOREIGN KEY(Cno) REFERENCES Courses
51 )
52 INSERT INTO Reports VALUES('S01','C01',92)
53 INSERT INTO Reports VALUES('S01','C03',84)
54 INSERT INTO Reports VALUES('S02','C01',90)
55 INSERT INTO Reports VALUES('S02','C02',94)
56 INSERT INTO Reports VALUES('S02','C03',82)
57 INSERT INTO Reports VALUES('S03','C01',72)
58 INSERT INTO Reports VALUES('S03','C02',90)
59 INSERT INTO Reports VALUES('S04','C03',75)

SELECT Sno,Sname
FROM Students
WHERE Dno IN
(SELECT DnoFROM DeptsWHERE Dname='数学'
)

SELECT DISTINCT Sno
FROM Reports

SELECT Sno,Grade
FROM Reports
WHERE Cno='C01'
ORDER BY Grade DESC,Sno 

SELECT Sno,Grade*0.8 NewGrade
FROM Reports
WHERE Cno='C01' AND Grade BETWEEN 80 AND 90

SELECT *
FROM Students
WHERE Sname LIKE'张%' AND Dno IN
(SELECT DnoFROM DeptsWHERE Dname='数学' OR Dname='计算机'
)

SELECT Students.* ,Reports.*
FROM Students,Reports
WHERE Students.Sno= Reports.Sno

SELECT Students.Sno,Sname,Cname,Grade
FROM Students,Reports,Courses,Depts
WHERE Students.Sno= Reports.Sno AND Reports.Cno=Courses.CnoAND Students.Dno=Depts.Dno

SELECT A.Cno,A.Cname,B.Pre_Cno
FROM Courses A,Courses B
WHERE A.Pre_Cno=B.Cno

SELECT *
FROM Students
WHERE Dno!=
(SELECT DnoFROM DeptsWHERE Dname='计算机'
) AND Sage<some(SELECT MAX(Sage)FROM StudentsWHERE Dno=(SELECT DnoFROM DeptsWHERE Dname='计算机'))

SELECT Sname
FROM Students
WHERE NOT EXISTS
(SELECT *FROM CoursesWHERE NOT EXISTS(SELECT *FROM ReportsWHERE Sno=Students.Sno AND Cno=Courses.Cno)
)

SELECT Sno,Sname
FROM Students
WHERE Sno IN
(SELECT DISTINCT SnoFROM Reports AWHERE NOT EXISTS(SELECT *FROM Reports BWHERE B.Sno='S03' AND NOT EXISTS(SELECT *FROM Reports CWHERE C.Sno=A.Sno AND C.Cno=B.Cno))
)