mysql 建数据库 建表

创建数据库：

create database td；

use database td；//在数据库td中创建表

创建表：

create table tb_student (
Student_ID int auto_increment primary key, //自增id，指定主键
Student_Name varchar(20), 
Sex char(1), 
Birthday varchar(10)
) engine=innodb default character set =utf8;//指定存储引擎和字符集



create table tb_score (
ID int auto_increment primary key,
Student_ID int,
Subject_ID int,
Score decimal(10,2),
foreign key (Student_ID) references tb_student(Student_ID),//指定外键
foreign key (Subject_ID) references tb_subject(Subject_ID)
) engine=innodb default character set =utf8;create table tb_subject (
Subject_ID int auto_increment primary key, 
Subject_Name varchar(50)
) engine=innodb default character set =utf8;