Mysql user management and authority management

Column catalog please click

User Management

create user

CREATE USER zhangsan IDENTIFIED BY '123456';

The execution results are as follows

view users

SELECT * FROM mysql.user;

field explanation

host

Indicates the type of connection

1. % means all remote connections via TCP
2. IP address such as (192.168.1.2, 127.0.0.1) TCP connection through specifying ip address
3. The machine name is a TCP connection made by specifying the machine name in the i network
4. ::1 The local ip address of IPv6 is equivalent to 127.0.0.1 of IPv4
5. localhost local connection via command line, such as mysql -u xxx -p 123xxx connection

User

Indicates username

The permissions linked by the same user through different methods are different.

select_priv , insert_priv etc

Permissions owned by this user.

change Password

Modify the current user password

SET PASSWORD =PASSWORD('123456')

Change a user's password

UPDATE mysql.user SET PASSWORD=PASSWORD('123123') WHERE USER='zhangsan';
FLUSH PRIVILEGES;   #所有通过user表的修改，必须用该命令才能生效。

modify user

UPDATE mysql.user SET USER='zhangsan' WHERE USER='zhangsi';
FLUSH PRIVILEGES;   #所有通过user表的修改，必须用该命令才能生效。

delete users

DROP USER zhangsan ;

pass

DELETE FROM  USER WHERE USER='zhangsan' 

User data will remain

authority management

View permissions

View current user permissions

SHOW GRANTS;

View a user's global permissions

select  * from user ;

View the permissions of a library for a user

select * from  db;

View the permissions of a table for a user

select * from tables_priv;

Granted permission

GRANT 权限1,权限2,…权限n ON 数据库名称.表名称 TO 用户名@用户地址 IDENTIFIED BY ‘连接口令’;

• If it is found that the user does not have this permission, a new user will be created directly

example one

GRANT SELECT,INSERT,DELETE,DROP ON hello.* TO zhangsan@localhost  ;

• Grant permission to insert, delete, modify and check all tables under the hello library

Example 2

GRANT ALL PRIVILEGES ON *.* TO joe@'%'  IDENTIFIED BY '123';

• Grant the joe user who logs in through the network, all permissions to all tables in all libraries, and the password is set to 123
• Even if all privileges have all permissions, grant_priv permissions can only be owned by root

Example three

Assign the link command to the root user

GRANT ALL PRIVILEGES ON *.* TO root@'%';

• The newly created connection does not have a password, and a password needs to be set to connect remotely.

UPDATE USER SET PASSWORD=PASSWORD('root') WHERE USER='root' AND HOST='%';

Withdraw authority

The user must log in again to take effect

REVOKE  权限1,权限2,…权限n ON 数据库名称.表名称  FROM  用户名@用户地址 ;

example one

REVOKE ALL PRIVILEGES ON mysql.* FROM joe@localhost;

Take back all permissions of the whole database and tables

Example 2

REVOKE select,insert,update,delete ON mysql.* FROM joe@localhost;

• Take back the permission to insert, delete, modify and query all tables under the mysql library