黑马程序员 MySQL数据库入门到精通，从mysql安装到mysql高级、mys
外键约束
CREATE TABLE dept(
id int auto_increment COMMENT 'ID' PRIMARY KEY,
name VARCHAR(50) not null COMMENT '部门名称'
)COMMENT '部门表';
INSERT INTO dept (id,name) VALUES (1,'研发部'),(2,'市场部'),(3,'财务部'),(4,'销售部'),(5,'总经办');
CREATE TABLE eml (
id INT AUTO_INCREMENT COMMENT 'ID' PRIMARY KEY,
NAME VARCHAR(50) NOT NULL COMMENT '姓名',
age INT COMMENT '年龄',
job VARCHAR(20) COMMENT '职位',
salary INT COMMENT '薪资',
entrydate date COMMENT '入职时间',
managerid INT COMMENT '直属领导ID',
dept_id INT COMMENT '部门'
) COMMENT '员工表';
INSERT INTO eml (id, name, age, job, salary, entrydate, managerid, dept_id)
VALUES
(1, '柳岩', 66, '总裁', 20000, '2000-01-01', NULL, 5),
(2, '张无忌', 20, '项目经理', 125000, '2005-09-01', 1, 1),
(3, '韦一笑', 33, '开发', 8400, '2005-08-01', 2, 1),
(4, '赵敏', 48, '开发', 11000, '2009-12-01', 2, 1),
(5, '小昭', 43, '开发', 6600, '2007-07-01', 3, 1),
(6, '奥特玛', 43, '程序员鼓励是', 6600, '2007-07-01', 2, 1);
# - 多对多
# **创建学生表**
CREATE TABLE student (
id INT AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(10) COMMENT '姓名',
no VARCHAR(10) COMMENT '学号'
) COMMENT '学生表';
INSERT INTO student VALUES
(null, '维练', '2088100101'),
(null, '谢逊', '2080100102'),
(null, '傲天正', '200100103'),
(null, '伟一肖', '200100104');
# **创建课程表**
CREATE TABLE course (
id INT AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(100) COMMENT '课程名称'
) COMMENT '课程表';
INSERT INTO course VALUES
(null, 'Java'),
(null, 'PHP'),
(null, 'MySQL'),
(null, 'Hadoop');
# **创建中间表**
CREATE TABLE student_course (
id INT AUTO_INCREMENT COMMENT '主键',
studentid INT NOT NULL COMMENT '学生ID',
courseid INT NOT NULL COMMENT '课程ID',
PRIMARY KEY (id),
CONSTRAINT fk_courseid FOREIGN KEY (courseid) REFERENCES course (id),
CONSTRAINT fk_studentid FOREIGN KEY (studentid) REFERENCES student (id)
) COMMENT '学生课程中间表';
INSERT INTO student_course VALUES
(null, 1, 1),
(null, 1, 2),
(null, 1, 3),
(null, 2, 2),
(null, 2, 3),
(null, 3, 4);
# - 一对一
# **创建用户基本信息表**
CREATE TABLE tb_user (
id INT AUTO_INCREMENT PRIMARY KEY COMMENT '主键ID',
name VARCHAR(10) COMMENT '姓名',
age INT COMMENT '年龄',
gender CHAR(1) COMMENT '1: 男，2: 女',
phone CHAR(11) COMMENT '手机号'
) COMMENT '用户基本信息表';
CREATE TABLE tb_user_edu(
id INT AUTO_INCREMENT PRIMARY KEY COMMENT '主键ID',
degree VARCHAR(20) COMMENT '学历',
major VARCHAR(50) COMMENT '专业',
primaryschool VARCHAR(50) COMMENT '小学',
middleschool VARCHAR(50) COMMENT '中学',
university VARCHAR(50) COMMENT '大学',
userid INT UNIQUE COMMENT '用户ID',
CONSTRAINT fk_userid FOREIGN KEY (userid) REFERENCES tb_user(id)
) COMMENT '用户教育信息表';
# **插入数据**
INSERT INTO tb_user(id, name, age, gender, phone) VALUES
(null, '黄渤', 45, '1', '18800001111'),
(null, '冰冰', 352, '1', '18800002222'),
(null, '码云', 55, '1', '18800008888'),
(null, '李彦宏', 50, '1', '18800009999');
INSERT INTO tb_user_edu(id, degree, major, primaryschool, middleschool, university, userid) VALUES
(null, '本科', '舞蹈', '静安区第一小学', '静安区第一中学', '北京舞蹈学院', 1),
(null, '硕士', '表演', '朝阳区第一小学', '朝阳区第一中学', '北京电影学院', 2),
(null, '本科', '英语', '杭州市第一小学', '杭州市第一中学', '杭州师范大学', 3),
(null, '本科', '应用数学', '阳泉第一小学', '阳泉区第一中学', '清华大学', 4);
