在mysql中生成数据库和数据表

#创建数据库
CREATE DATABASE s4day65 DEFAULT CHARSET utf8;

#班级表
CREATE TABLE class (id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,title CHAR(20))
ENGINE=INNODB DEFAULT CHARSET=utf8;

#学生表    有一个指向班级表的外键
CREATE TABLE student (id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
NAME CHAR(20),
class_id INT,
CONSTRAINT fk_s_c FOREIGN KEY (class_id) REFERENCES class(id)
)ENGINE=INNODB DEFAULT CHARSET=utf8;

#教师表    
CREATE TABLE teacher (id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
NAME CHAR(20))ENGINE=INNODB DEFAULT CHARSET=utf8;

#教师和班级关系表
CREATE TABLE teacher2class(id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
class_id INT,teacher_id INT)ENGINE=INNODB DEFAULT CHARSET=utf8;