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Mysql data control language

Aug 09, 2017 pm 03:06 PM
mysqldatalanguage

Mysql data control language

1. Data control language

User management:

Storage location of user information:

Users in mysql are stored in the system database "mysql" of the mysql system.

Mysql data control language


##2. Create user:

create user 'Username'@'Location allowed to log in' identified by 'Password'

Example:

Mysql data control language


3. Delete user:

drop user ' Username '@' Allowed login location';

Modify user password:

Modify own password:

set  password  = password(‘新密码’);

Modify other people's passwords (with permission) :


set  password  for  ‘用户名’@’允许登录的位置’  = password(‘新密码’);


4. Permission management:

What are permissions?

Permission is the right to do something, such as "insert", create, update, and delete. . . .

"all" means "all permissions"

In fact, in the mysql system, permissions are the above-mentioned "words";

What permissions are there?

Mysql data control language

5. Refined to:

Mysql data control language


##6. Grant user permissions

grant permission 1, permission 2, .... on a certain library. A subordinate unit to ' User name '@' allows login location' [identified by 'password']

Description:

1, permission names include: insert, update, select, delete, create, drop. .....

2, "A certain subordinate unit" refers to the subordinate data elements in a library. Currently we have only learned 2: table, view;

For example: php44. The student table or php44.int_test

has two special writing methods:

*.*: indicates all subordinate units in all databases;

a certain library.*: indicates the All subordinate units in the database

3. If permissions are granted to existing users, the identified part can be omitted. If not omitted, it means changing their password;

And for a new user (That is, 'username'@'location where login is allowed' does not actually exist yet), the identified part cannot be omitted, and the grant statement actually creates a new user!

Mysql data control language##7. You can also grant "all permissions":

grant all privileges on php44.* to 'user1'@'192.168.44.64';
Cancel user permissions

revoke Permission 1, Permission 2, .... on a library. A subordinate unit from 'Username'@'Location where login is allowed'

Description:

1 Each item The meaning is the same as the grant statement;

2 means to cancel certain permissions of a certain user on a certain data unit.

The above is the detailed content of Mysql data control language. For more information, please follow other related articles on the PHP Chinese website!

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