1 --建表
 2 --student表+注释
 3 create table student(
 4        sno   varchar2(3) not null,
 5        sname varchar2(9) not null,
 6        ssex  varchar2(3) not null,
 7        sbirthday date,
 8        sclass varchar2(5),
 9        constraint pk_student primary key(sno)
10 );
11 comment on column student.sno is '学号（主键）';
12 comment on column student.sname is '学生姓名';
13 comment on column student.ssex is '学生性别';
14 comment on column student.sbirthday is '学生出生年月日';
15 comment on column student.sclass is '学生所在班级';

16 --course表+注释
17 create table course(
18        cno       varchar2(5) not null,
19        cname     varchar2(15) not null,
20        tno       varchar2(3) not null,
21        constraint pk_course primary key(cno)
22 );
23 comment on column course.cno is '课程编号（主键）';
24 comment on column course.cname is '课程名称';
25 comment on column course.tno is '教工编号（外键）';

26 --score表+注释
27 create table score(
28         sno   varchar2(3) not null,
29         cno   varchar2(5) not null,
30         degree   number(4,1),
31         constraint pk_score primary key(sno,cno)
32 );
33 comment on column score.sno is '学号（主键）';
34 comment on column score.cno is '课程编号（主键）';
35 comment on column score.degree is '成绩';

36 --teacher表+注释
37 create table teacher(
38        tno   varchar2(3) not null,
39        tname varchar2(9) not null,
40        tsex  varchar2(3) not null,
41        tbirthday date,
42        prof  varchar2(9),
43        depart varchar2(15) not null,
44        constraint pk_teacher primary key(tno)
45 );
46 comment on column teacher.tno is '教工编号（主键）';
47 comment on column teacher.tname is '教工姓名';
48 comment on column teacher.tsex is '教工性别';
49 comment on column teacher.tbirthday is '教工出生年月';
50 comment on column teacher.prof is '职称';
51 comment on column teacher.depart is '教工所在单位';

52 --添加外键
53 alter table course add constraint fk_tno foreign key(tno) references teacher(tno);
54 alter table score add constraint fk_sno foreign key(sno) references student(sno);
55 alter table score add constraint fk_cno foreign key(cno) references course(cno); 

56 --添加数据
57 --Student表
58 insert into student(sno,sname,ssex,sbirthday,sclass) values(108,'曾华','男',to_date('1977-09-01','yyyy-mm-dd'),95033);
59 insert into student(sno,sname,ssex,sbirthday,sclass) values(105,'匡明','男',to_date('1975-10-02','yyyy-mm-dd'),95031);
60 insert into student(sno,sname,ssex,sbirthday,sclass) values(107,'王丽','女',to_date('1976-01-23','yyyy-mm-dd'),95033);
61 insert into student(sno,sname,ssex,sbirthday,sclass) values(101,'李军','男',to_date('1976-02-20','yyyy-mm-dd'),95033);
62 insert into student(sno,sname,ssex,sbirthday,sclass) values(109,'王芳','女',to_date('1975-02-10','yyyy-mm-dd'),95031);
63 insert into student(sno,sname,ssex,sbirthday,sclass) values(103,'陆君','男',to_date('1974-06-03','yyyy-mm-dd'),95031);

64 --teacher表
65 insert into teacher(tno,tname,tsex,tbirthday,prof,depart) values(804,'李诚','男',to_date('1958/12/02','yyyy-mm-dd'),'副教授','计算机系');
66 insert into teacher(tno,tname,tsex,tbirthday,prof,depart) values(856,'张旭','男',to_date('1969/03/12','yyyy-mm-dd'),'讲师','电子工程系');
67 insert into teacher(tno,tname,tsex,tbirthday,prof,depart) values(825,'王萍','女',to_date('1972/05/05','yyyy-mm-dd'),'助教','计算机系');
68 insert into teacher(tno,tname,tsex,tbirthday,prof,depart) values(831,'刘冰','女',to_date('1977/08/14','yyyy-mm-dd'),'助教','电子工程系');

69 --course表(添加外键后要先填teacher表中数据去满足外键约束)
70 insert into course(cno,cname,tno) values('3-105','计算机导论',825);
71 insert into course(cno,cname,tno) values('3-245','操作系统',804);
72 insert into course(cno,cname,tno) values('6-166','数字电路',856);
73 insert into course(cno,cname,tno) values('9-888','高等数学',831);

74 --score表（添加外键后要先填Student，course表中数据去满足外键约束）
75 insert into score(sno,cno,degree) values(103,'3-245',86);
76 insert into score(sno,cno,degree) values(105,'3-245',75);
77 insert into score(sno,cno,degree) values(109,'3-245',68);
78 insert into score(sno,cno,degree) values(103,'3-105',92);
79 insert into score(sno,cno,degree) values(105,'3-105',88);
80 insert into score(sno,cno,degree) values(109,'3-105',76);
81 insert into score(sno,cno,degree) values(101,'3-105',64);
82 insert into score(sno,cno,degree) values(107,'3-105',91);
83 insert into score(sno,cno,degree) values(108,'3-105',78);
84 insert into score(sno,cno,degree) values(101,'6-166',85);
85 insert into score(sno,cno,degree) values(107,'6-166',79);
86 insert into score(sno,cno,degree) values(108,'6-166',81);