标签：without 说明 databases load data mysqld nbsp iat column ase
1.创建用户
CREATE USER ‘username‘@‘host‘ IDENTIFIED BY ‘password‘;
2.用户授权
GRANT privileges ON databasename.tablename TO ‘username‘@‘host‘;
说明: privileges - 用户的操作权限,如SELECT , INSERT , UPDATE 等(详细列表见该文最后面).如果要授予所的权限则使用ALL.;databasename - 数据库名,tablename-表名,如果要授予该用户对所有数据库和表的相应操作权限则可用*表示, 如*.*.
例子:
GRANT SELECT, INSERT ON test.user TO ‘pig‘@‘%‘; GRANT ALL ON *.* TO ‘pig‘@‘%‘;
注意:用以上命令授权的用户不能给其它用户授权,如果想让该用户可以授权,用以下命令:
GRANT privileges ON databasename.tablename TO ‘username‘@‘host‘ WITH GRANT OPTION;
3.取消授权
REVOKE privilege ON databasename.tablename FROM ‘username‘@‘host‘;
说明: privilege, databasename, tablename - 同授权部分.
例子:
REVOKE SELECT ON *.* FROM ‘pig‘@‘%‘;
注意: 假如你在给用户‘pig‘@‘%‘授权的时候是这样的(或类似的):GRANT SELECT ON test.user TO ‘pig‘@‘%‘, 则在使用REVOKE SELECT ON *.* FROM ‘pig‘@‘%‘;命令并不能撤销该用户对test数据库中user表的SELECT 操作.相反,如果授权使用的是GRANT SELECT ON *.* TO ‘pig‘@‘%‘;则REVOKE SELECT ON test.user FROM ‘pig‘@‘%‘;命令也不能撤销该用户对test数据库中user表的Select 权限.
具体信息可以用命令 SHOW GRANTS FOR ‘pig‘@‘%‘; 查看.
4.设置或修改密码
SET PASSWORD FOR ‘username‘@‘host‘ = PASSWORD(‘newpassword‘);
如果是当前登陆用户用 SET PASSWORD = PASSWORD("newpassword");
例子:
SET PASSWORD FOR ‘pig‘@‘%‘ = PASSWORD("123456");
如果忘记root密码，操作如下：
1).linux切换到root用户
2).修改MySql的登陆设置，编辑my.cnf文件
[root@promote /]# vi /etc/my.cnf
在[mysqld]字段下加入一句： skip-grant-tables
保存退出。
3).重新启动mysqld
[root@promote /]# service mysqld restart
4).之后可以免密码进入MySql，然后use mysql
[root@promote /]# mysql Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 3 Server version: 5.7.18 MySQL Community Server (GPL) Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type ‘help;‘ or ‘\h‘ for help. Type ‘\c‘ to clear the current input statement. mysql> use mysql; Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A Database changed
5).修改root用户密码
mysql> update mysql.user set authentication_string=password(‘root‘) where User=‘root‘ and Host=‘localhost‘; Query OK, 1 row affected, 1 warning (0.00 sec) Rows matched: 1 Changed: 1 Warnings: 1
6).退出MySql，编辑my.cnf，删除skip-grant-tables一行
7).可用root用户的新密码登进MySql
5.删除用户
DROP USER ‘username‘@‘host‘;
附表：在MySql中的操作权限
标签：without 说明 databases load data mysqld nbsp iat column ase
原文地址：http://www.cnblogs.com/luojunc/p/6979775.html
