在写一个简单的 没有组的 create table _user( id int primary key auto_increment, passwd varchar(10) not null, name varchar(20) not null, sign varchar(200) );
alter table _user auto_increment 1000;
create table _firend( owner int not null, firend int not null, primary key(owner,firend), foreign key(owner) references _user(id) on delete cascade on update cascade, foreign key(firend) references _user(id) on delete cascade on update cascade );
create table _user(
id int primary key auto_increment,
passwd varchar(10) not null,
name varchar(20) not null,
sign varchar(200)
);
alter table _user auto_increment 1000;
create table _firend(
owner int not null,
firend int not null,
primary key(owner,firend),
foreign key(owner) references _user(id) on delete cascade on update cascade,
foreign key(firend) references _user(id) on delete cascade on update cascade
);
组ID
组名
...一个 好友表
好友ID
组ID
好友名
...