创建students表关联country,position,gender三张表
create table country(
cid int primary key auto_increment,
cname varchar(10) NOT NULL
)ENGINE=INNODB DEFAULT CHARSET=utf8;
create table `position`(
pid int primary key auto_increment,
pname varchar(10) NOT NULL
)ENGINE=INNODB DEFAULT CHARSET=utf8;
create table Gender(
gid int primary key auto_increment,
gname varchar(10) NOT NULL
)ENGINE=INNODB DEFAULT CHARSET=utf8;
create table students(
sid int primary key auto_increment,
sname varchar(100) not null,
countryId int,
positionId int,
GenderId int,
Capability int,
constraint fk_stu_cid foreign key(countryId)
references country(cid),
constraint fk_stu_pid foreign key(positionId)
references `position`(pid),
constraint fk_stu_gid foreign key(GenderId)
references Gender(gid)
)ENGINE=INNODB DEFAULT CHARSET=utf8;
insert into students(sname,countryId,positionId,GenderId,Capability) values('刘备',3,2,1,80);
insert into students(sname,countryId,positionId,GenderId,Capability) values('曹操',1,1,1,76);
id name countryId positionId GenderId Capability
刘备 蜀 打野 男 80
曹操 魏 top 男 76
孙策
孙尚香 吴 AD 女 88
诸葛亮 蜀 ap 男 87
周瑜
黄忠
关羽
张飞
赵云
小乔
大乔
貂蝉
吕布
夏侯惇
insert into country(cname) values('魏');
id country
1 魏
2 蜀
3 吴
insert into `position`(pname) values('top');
insert into `position`(pname) values('jungle');
insert into `position`(pname) values('ap');
insert into `position`(pname) values('ad');
insert into `position`(pname) values('sup');
id position
1 top
2 jungle
3 ap
4 ad
5 sup
insert into Gender(gname) values('男');
insert into Gender(gname) values('女');
id Gender
1 female
2 male
查询
select * from students s,country c,position p,Gender g where s.countryId = c.cid and s.positionId = p.pid and s.GenderId = g.gid;