oracle命令建立主键外键
1、创建一张学生表
[sql]
SQL> create table t_stu(
2 stuid number(10) primary key,
3 stuname varchar2(20) not null,
4 stusex varchar2(2) default '男' check(stusex in('男','女')));
Table created
Executed in 0.547 seconds
2、创建一张课程表
[sql]
SQL> create table t_couse(
2 couseid number(10) primary key,
3 cousename varchar2(20) not null,
4 cousetype varchar2(4));
www.2cto.com
Table created
Executed in 0.062 seconds
3、创建一张学生课程成绩表（包括主外键）
[sql]
SQL> create table t_score(
2 scoreid number(10) primary key,
3 stuid number(10) references t_stu(stuid),
4 couseid number(10),
5 constraint fk_couseid foreign key(couseid)
6 references t_couse(couseid)
7 on delete cascade);
Table created