1.创建外键，关联两个表create table score( id int not null auto_increment, subject char(32) not null,
1.创建外键，关联两个表
create table score( id int not null auto_increment, subject char(32) not null, stu_id int not null, primary key(id), key fk_stu_key (stu_id), constraint fk_stu_key foreign key (stu_id) references student (stu_id));