1.MySQL用户，权限管理
1）用户作用
Linux用户的作用
a.登陆系统
b.管理操作系统对象（文件/目录）
mysql用户的作用：
a.登陆mysql
b.管理mysql的对象（库/表）
2）用户表现方式
Linux用户表现方式：用户名
mysql用户的表现方式：用户名@'白名单'
3）用户管理：
mysql> create user fake@'10.0.0.%' identified by '123';
Query OK, 0 rows affected (0.00 sec)
mysql> drop user fake@'10.0.0.%';
Query OK, 0 rows affected (0.00 sec)
mysql> select user,host,password from mysql.user;
mysql>set password for fake@'10.0.0.%'=PASSWORD('456');
多实例（多个数据库管理系统）应用
准备：
多个专用目录：
[root@db01 ~]# mkdir /data/330{7..9}/data多个配置文件：
vim /data/3307/my.cnf
[mysqld]
basedir=/application/mysql
datadir=/data/3307/data
socket=/data/3307/mysql.sock
port=3307
log-error=/data/3307/mysql.log
skip-name-resolve
server-id=7
--------------------------
vim /data/3308/my.cnf
[mysqld]
basedir=/application/mysql
datadir=/data/3308/data
port=3308
socket=/data/3308/mysql.sock
log-error=/data/3308/mysql.log
skip-name-resolve
server-id=8
------------------
vim /data/3309/my.cnf
[mysqld]
basedir=/application/mysql
datadir=/data/3309/data
socket=/data/3309/mysql.sock
port=3309
log-error=/data/3309/mysql.log
skip-name-resolve
server-id=9
初始化多次数据库：
/application/mysql/scripts/mysql_install_db --user=mysql --basedir=/application/mysql --datadir=/data/3307/data
/application/mysql/scripts/mysql_install_db --user=mysql --basedir=/application/mysql --datadir=/data/3308/data
/application/mysql/scripts/mysql_install_db --user=mysql --basedir=/application/mysql --datadir=/data/3309/data
修改权限：
touch /data/330{7..9}/mysql.log
chown -R mysql.mysql /data/330*启动数据库：
/application/mysql/bin/mysqld_safe --defaults-file=/data/3307/my.cnf &
/application/mysql/bin/mysqld_safe --defaults-file=/data/3308/my.cnf &
/application/mysql/bin/mysqld_safe --defaults-file=/data/3309/my.cnf &
验证：
[root@db01 ~]# netstat -lnp|grep 330
tcp6 0 0 :::3306 :::* LISTEN 30972/mysqld
tcp6 0 0 :::3307 :::* LISTEN 31472/mysqld
tcp6 0 0 :::3308 :::* LISTEN 31461/mysqld
unix 2 [ ACC ] STREAM LISTENING 218904 31472/mysqld /data/3307/mysql.sock
unix 2 [ ACC ] STREAM LISTENING 218889 31461/mysqld /data/3308/mysql.sock
[root@db01 ~]#
[root@db01 ~]# mysql -S /data/3307/mysql.sock -e "show variables like 'server_id'"
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| server_id | 7 |
+---------------+-------+
[root@db01 ~]# mysql -S /data/3308/mysql.sock -e "show variables like 'server_id'"
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| server_id | 8 |
+---------------+-------+
[root@db01 ~]# mysql -S /data/3309/mysql.sock -e "show variables like 'server_id'"
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| server_id | 9 |
+---------------+-------+
