一、查看MYSQL数据库中所有用户及拥有权限1.查看MYSQL数据库中所有用户
mysql> SELECT DISTINCT CONCAT('User: ''',user,'''@''',host,''';') AS query FROM mysql.user;
+---------------------------------+
| query |
+---------------------------------+
| User: 'anemometer'@'%'; |
| User: 'root'@'%'; |
| User: 'zabbix-monitor'@'%'; |
| User: 'root'@'127.0.0.1'; |
| User: 'root'@'192.168.1.90'; |
| User: 'root'@'::1'; |
| User: 'anemometer'@'localhost'; |
| User: 'redmine'@'localhost'; |
| User: 'root'@'localhost'; |
| User: 'zabbix'@'localhost'; |
+---------------------------------+
10 rows in set (0.00 sec)
2.查看数据库中具体某个用户的权限mysql> show grants for 'anemometer'@'%'; +------------------------------------------------------------------------------------------------------------+ | Grants for anemometer@% | +------------------------------------------------------------------------------------------------------------+ | GRANT SELECT ON *.* TO 'anemometer'@'%' IDENTIFIED BY PASSWORD '*3E68D69BA58D0A50F00FCCF5F15DEDC9EBD432EA' | | GRANT ALL PRIVILEGES ON `slow_query_log`.* TO 'anemometer'@'%' | +------------------------------------------------------------------------------------------------------------+ 2 rows in set (0.00 sec)
mysql> select * from mysql.user where user='anemometer' \G
*************************** 1. row ***************************
Host: localhost
User: anemometer
Password: *3E68D69BA58D0A50F00FCCF5F15DEDC9EBD432EA
Select_priv: Y
Insert_priv: N
Update_priv: N
Delete_priv: N
Create_priv: N
Drop_priv: N
Reload_priv: N
Shutdown_priv: N
Process_priv: N
File_priv: N
Grant_priv: N
References_priv: N
Index_priv: N
Alter_priv: N
Show_db_priv: N
Super_priv: N
Create_tmp_table_priv: N
Lock_tables_priv: N
Execute_priv: N
Repl_slave_priv: N
Repl_client_priv: N
Create_view_priv: N
Show_view_priv: N
Create_routine_priv: N
3.查看user表结构 需要具体的项可结合表结构来查询
mysql> desc mysql.user;
+------------------------+-----------------------------------+------+-----+-----------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------+-----------------------------------+------+-----+-----------------------+-------+
| Host | char(60) | NO | PRI | | |
| User | char(16) | NO | PRI | | |
| Password | char(41) | NO | | | |
| Select_priv | enum('N','Y') | NO | | N | |
| Insert_priv | enum('N','Y') | NO | | N | |
| Update_priv | enum('N','Y') | NO | | N | |
| Delete_priv | enum('N','Y') | NO | | N | |
| Create_priv | enum('N','Y') | NO | | N | |
| Drop_priv | enum('N','Y') | NO | | N | |
| Reload_priv | enum('N','Y') | NO | | N | |
| Shutdown_priv | enum('N','Y') | NO
Process_priv | enum('N','Y') | NO | | N | |
| File_priv | enum('N','Y') | NO | | N | |
| Grant_priv | enum('N','Y') | NO | | N | |
| References_priv | enum('N','Y') | NO | | N | |
| Index_priv | enum('N','Y') | NO | | N | |
| Alter_priv | enum('N','Y') | NO | | N | |
| Show_db_priv | enum('N','Y') | NO | | N | |
| Super_priv | enum('N','Y') | NO | | N | |
| Create_tmp_table_priv | enum('N','Y') | NO | | N | |
| Lock_tables_priv | enum('N','Y') | NO | | N | |
| Execute_priv | enum('N','Y') | NO | | N | |
| Repl_slave_priv | enum('N','Y') | NO | | N | |
| Repl_client_priv | enum('N','Y') | NO | | N | |
| Create_view_priv | enum('N','Y') | NO | | N | |
| Show_view_priv | enum('N','Y') | NO | | N | |
| Create_routine_priv | enum('N','Y') | NO | | N | |
| Alter_routine_priv | enum('N','Y') | NO | | N | |
| Create_user_priv | enum('N','Y') | NO | | N | |
| Event_priv | enum('N','Y') | NO | | N | |
| Trigger_priv | enum('N','Y') | NO | | N | |
| Create_tablespace_priv | enum('N','Y') | NO | | N | |
| ssl_type | enum('','ANY','X509','SPECIFIED') | NO | | | |
| ssl_cipher | blob | NO | | NULL | |
| x509_issuer | blob | NO | | NULL | |
| x509_subject | blob | NO | | NULL | |
| max_questions | int(11) unsigned | NO | | 0 | |
| max_updates | int(11) unsigned | NO | | 0 | |
| max_connections | int(11) unsigned | NO | | 0 | |
| max_user_connections | int(11) unsigned | NO | | 0 | |
| plugin | char(64) | YES | | mysql_native_password | |
| authentication_string | text | YES | | NULL | |
| password_expired | enum('N','Y') | NO | | N | |
+------------------------+-----------------------------------+------+-----+-----------------------+-------+
43 rows in set (0.01 sec)
二、用户权限管理主要有以下作用：
1. 可以限制用户访问哪些库、哪些表 （一）、用户授权mysql> grant all privileges on *.* to 'alex'@'%' identified by '123456' with grant option; •all privileges：表示将所有权限授予给用户。也可指定具体的权限，如：SELECT、CREATE、DROP等。 •on：表示这些权限对哪些数据库和表生效，格式：数据库名.表名，这里写“*”表示所有数据库，所有表。如果我要指定将权限应用到test库的user表中，可以这么写：test.user •to：将权限授予哪个用户。格式：”用户名”@”登录IP或域名”。%表示没有限制，在任何主机都可以登录。比如：”alex”@”192.168.0.%”，表示alex这个用户只能在192.168.0IP段登录 •identified by：指定用户的登录密码 •with grant option：表示允许用户将自己的权限授权给其它用户 可以使用GRANT给用户添加权限，权限会自动叠加，不会覆盖之前授予的权限，比如你先给用户添加一个SELECT权限，后来又给用户添加了一个INSERT权限，那么该用户就同时拥有了SELECT和INSERT权限。 （二）、刷新权限对用户做了权限变更之后，一定记得重新加载一下权限，将权限信息从内存中写入数据库。 mysql> flush privileges; （三）、查看用户权限（同前文所叙）（四）、回收权限删除alex这个用户的create权限，该用户将不能创建数据库和表。 mysql> revoke create on *.* from 'alex@localhost'; mysql> flush privileges; (五)、删除用户mysql> select host,user from user; +---------------+---------+ | host | user | +---------------+---------+ | % | root | | % | test3 | | % | yx | | 192.168.0.% | root | | 192.168.0.% | test2 | | 192.168.0.109 | test | | ::1 | alex | | localhost | alex | +---------------+---------+ 8 rows in set (0.00 sec) mysql> drop user 'alex'@'localhost'; (六)、用户重命名shell> rename user 'test3'@'%' to 'test1'@'%'; (七)、修改密码
1> 更新mysql.user表
mysql> use mysql;
# mysql5.7之前
mysql> update user set password=password('123456') where user='root';
# mysql5.7之后
mysql> update user set authentication_string=password('123456') where user='root';
mysql> flush privileges;
2> 用set password命令
语法：set password for ‘用户名'@'登录地址'=password(‘密码')
mysql> set password for 'root'@'localhost'=password('123456');
3> mysqladmin
语法：mysqladmin -u用户名 -p旧的密码 password 新密码
mysql> mysqladmin -uroot -p123456 password 1234abcd
注意：mysqladmin位于mysql安装目录的bin目录下
(八)、忘记密码1> 添加登录跳过权限检查配置 修改my.cnf，在mysqld配置节点添加skip-grant-tables配置 [mysqld] skip-grant-tables 2> 重新启动mysql服务 shell> service mysqld restart 3> 修改密码 此时在终端用mysql命令登录时不需要用户密码，然后按照修改密码的第一种方式将密码修改即可。
4> 还原登录权限跳过检查配置 将my.cnf中mysqld节点的skip-grant-tables配置删除，然后重新启动服务即可。 注：段一参考自：http://blog.chinaunix.net/uid-21505614-id-302263.html 段二参考自：http://www.jb51.net/article/87979.htm (责任编辑：IT) |
