表操作练习题：练习：用户表，用户组表，主机表，业务线表 关联：用户与用户组 主机与业务线 用户与主机 # 用户表create table user( id int not null unique auto_increment, username varchar(20) not null, password varchar(50) not null, primary key(username,password));insert into user(username,password) values(‘root‘,‘123‘),(‘egon‘,‘456‘),(‘alex‘,‘alex3714‘);mysql> desc user;+----------+-------------+------+-----+---------+----------------+| Field | Type | Null | Key | Default | Extra |+----------+-------------+------+-----+---------+----------------+| id | int(11) | NO | UNI | NULL | auto_increment || username | varchar(20) | NO | PRI | NULL | || password | varchar(50) | NO | PRI | NULL | |+----------+-------------+------+-----+---------+----------------+3 rows in set (0.00 sec) mysql> select * from user;+----+----------+----------+| id | username | password |+----+----------+----------+| 1 | root | 123 || 2 | egon | 456 || 3 | alex | alex3714 |+----+----------+----------+3 rows in set (0.00 sec) # 用户组表create table usergroup( id int primary key auto_increment, groupname varchar(20) not null unique);insert into usergroup(groupname) values(‘IT‘),(‘Sale‘),(‘Finance‘),(‘Boss‘);mysql> desc usergroup;+-----------+-------------+------+-----+---------+----------------+| Field | Type | Null | Key | Default | Extra |+-----------+-------------+------+-----+---------+----------------+| id | int(11) | NO | PRI | NULL | auto_increment || groupname | varchar(20) | NO | UNI | NULL | |+-----------+-------------+------+-----+---------+----------------+2 rows in set (0.00 sec) mysql> select * from usergroup;+----+-----------+| id | groupname |+----+-----------+| 4 | Boss || 3 | Finance || 1 | IT || 2 | Sale |+----+-----------+4 rows in set (0.01 sec) # 主机表create table host( id int primary key auto_increment, ip char(15) not null unique default ‘127.0.0.1‘);insert into host(ip) values(‘172.16.45.2‘),(‘172.16.31.10‘),(‘172.16.45.3‘),(‘172.16.31.11‘),(‘172.10.45.3‘),(‘172.10.45.4‘),(‘172.10.45.5‘),(‘192.168.1.20‘),(‘192.168.1.21‘),(‘192.168.1.22‘),(‘192.168.2.23‘),(‘192.168.2.223‘),(‘192.168.2.24‘),(‘192.168.3.22‘),(‘192.168.3.23‘),(‘192.168.3.24‘);mysql> desc host;+-------+----------+------+-----+-----------+----------------+| Field | Type | Null | Key | Default | Extra |+-------+----------+------+-----+-----------+----------------+| id | int(11) | NO | PRI | NULL | auto_increment || ip | char(15) | NO | UNI | 127.0.0.1 | |+-------+----------+------+-----+-----------+----------------+2 rows in set (0.00 sec) mysql> select * from host;+----+---------------+| id | ip |+----+---------------+| 5 | 172.10.45.3 || 6 | 172.10.45.4 || 7 | 172.10.45.5 || 2 | 172.16.31.10 || 4 | 172.16.31.11 || 1 | 172.16.45.2 || 3 | 172.16.45.3 || 8 | 192.168.1.20 || 9 | 192.168.1.21 || 10 | 192.168.1.22 || 12 | 192.168.2.223 || 11 | 192.168.2.23 || 13 | 192.168.2.24 || 14 | 192.168.3.22 || 15 | 192.168.3.23 || 16 | 192.168.3.24 |+----+---------------+16 rows in set (0.01 sec) # 业务线表create table business( id int primary key auto_increment, business varchar(20) not null unique);insert into business(business) values(‘轻松贷‘),(‘随便花‘),(‘大富翁‘),(‘穷一生‘);mysql> desc business;+----------+-------------+------+-----+---------+----------------+| Field | Type | Null | Key | Default | Extra |+----------+-------------+------+-----+---------+----------------+| id | int(11) | NO | PRI | NULL | auto_increment || business | varchar(20) | NO | UNI | NULL | |+----------+-------------+------+-----+---------+----------------+2 rows in set (0.00 sec) mysql> select * from business;+----+-----------+| id | business |+----+-----------+| 3 | 大富翁 || 4 | 穷一生 || 1 | 轻松贷 || 2 | 随便花 |+----+-----------+4 rows in set (0.00 sec) # 建关系 user usergroupcreate table user2usergroup( id int not null unique auto_increment , user_id int not null, group_id int not null, primary key(user_id,group_id), foreign key(user_id) references user(id) on delete cascade on update cascade, foreign key(group_id) references usergroup(id) on delete cascade on update cascade);insert into user2usergroup(user_id,group_id) values(1,1),(1,2),(1,3),(1,4),(2,3),(2,4),(3,4);mysql> desc user2usergroup;+----------+---------+------+-----+---------+----------------+| Field | Type | Null | Key | Default | Extra |+----------+---------+------+-----+---------+----------------+| id | int(11) | NO | UNI | NULL | auto_increment || user_id | int(11) | NO | PRI | NULL | || group_id | int(11) | NO | PRI | NULL | |+----------+---------+------+-----+---------+----------------+3 rows in set (0.00 sec) mysql> select * from user2usergroup;+----+---------+----------+| id | user_id | group_id |+----+---------+----------+| 1 | 1 | 1 || 2 | 1 | 2 || 3 | 1 | 3 || 4 | 1 | 4 || 5 | 2 | 3 || 6 | 2 | 4 || 7 | 3 | 4 |+----+---------+----------+7 rows in set (0.00 sec) # 建关系 host businesscreate table host2business( id int not null unique auto_increment, host_id int not null, business_id int not null, primary key(host_id,business_id), foreign key(host_id) references host(id) on delete cascade on update cascade, foreign key(business_id) references business(id) on delete cascade on update cascade);insert into host2business(host_id,business_id) values(1,1),(1,2),(1,3),(2,2),(2,3),(3,4);mysql> desc host2business;+-------------+---------+------+-----+---------+----------------+| Field | Type | Null | Key | Default | Extra |+-------------+---------+------+-----+---------+----------------+| id | int(11) | NO | UNI | NULL | auto_increment || host_id | int(11) | NO | PRI | NULL | || business_id | int(11) | NO | PRI | NULL | |+-------------+---------+------+-----+---------+----------------+3 rows in set (0.00 sec) mysql> select * from host2business;+----+---------+-------------+| id | host_id | business_id |+----+---------+-------------+| 1 | 1 | 1 || 2 | 1 | 2 || 3 | 1 | 3 || 4 | 2 | 2 || 5 | 2 | 3 || 6 | 3 | 4 |+----+---------+-------------+6 rows in set (0.00 sec) # 建关系 user hostcreate table user2host( id int not null unique auto_increment, user_id int not null, host_id int not null, primary key(user_id,host_id), foreign key(user_id) references user(id) on delete cascade on update cascade, foreign key(host_id) references host(id) on delete cascade on update cascade);insert into user2host(user_id,host_id) values(1,1),(1,2),(1,3),(1,4),(1,5),(1,6),(1,7),(1,8),(1,9),(1,10),(1,11),(1,12),(1,13),(1,14),(1,15),(1,16),(2,2),(2,3),(2,4),(2,5),(3,10),(3,11),(3,12);mysql> desc user2host;+---------+---------+------+-----+---------+----------------+| Field | Type | Null | Key | Default | Extra |+---------+---------+------+-----+---------+----------------+| id | int(11) | NO | UNI | NULL | auto_increment || user_id | int(11) | NO | PRI | NULL | || host_id | int(11) | NO | PRI | NULL | |+---------+---------+------+-----+---------+----------------+3 rows in set (0.00 sec) mysql> select * from user2host;+----+---------+---------+| id | user_id | host_id |+----+---------+---------+| 1 | 1 | 1 || 2 | 1 | 2 || 3 | 1 | 3 || 4 | 1 | 4 || 5 | 1 | 5 || 6 | 1 | 6 || 7 | 1 | 7 || 8 | 1 | 8 || 9 | 1 | 9 || 10 | 1 | 10 || 11 | 1 | 11 || 12 | 1 | 12 || 13 | 1 | 13 || 14 | 1 | 14 || 15 | 1 | 15 || 16 | 1 | 16 || 17 | 2 | 2 || 18 | 2 | 3 || 19 | 2 | 4 || 20 | 2 | 5 || 21 | 3 | 10 || 22 | 3 | 11 || 23 | 3 | 12 |+----+---------+---------+23 rows in set (0.00 sec)
原文地址：https://www.cnblogs.com/alice-bj/p/8830569.html
时间： 2024-10-24 22:14:49