How to cancel all permissions in mysql-Mysql Tutorial-php.cn

In mysql, you can use the REVOKE statement to delete the permissions of a specified user (specified permissions or all permissions). The syntax to cancel all permissions is "REVOKE ALL PRIVILEGES, GRANT OPTION FROM user;". For the REVOKE statement to take effect, you must have the global CREATE USER permission or UPDATE permission of the MySQL database.

How to cancel all permissions in mysql

The operating environment of this tutorial: windows7 system, mysql8 version, Dell G3 computer.

In MySQL, you can use theREVOKEstatement to delete some or all permissions of a user.

Delete all permissions of a specific user, the syntax format is as follows:

REVOKE ALL PRIVILEGES, GRANT OPTION FROM 用户;

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You need to pay attention to the following points when deleting user permissions:

## The #REVOKE syntax is similar to the GRANT statement, but has the opposite effect.
To use the REVOKE statement, you must have global CREATE USER permission or UPDATE permission on the MySQL database.

Example:Assume that the rfc user has SELECT, UPDATE, and DELETE permissions on the sample database.

To revoke all permissions from the rfc user, execute the following command:

REVOKE ALL PRIVILEGES, GRANT OPTION FROM rfc;

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If rfc checks the user's permissions again, you will see that the rfc user has no permissions.

SHOW GRANTS FOR rfc; GRANT USAGE ON *.* TO 'rfc'@'%';

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Note: USAGE permissions means there are no permissions in MySQL.

When the MySQL REVOKE command takes effect

The effect of the MySQL REVOKE statement depends on the permission level, as follows:

Changes to global privileges only take effect when the client connects to MySQL in subsequent sessions. Changes will not be applied to all currently connected users.
Apply changes to database permissions after the next USE statement.
Changes to table and column permissions will apply to all queries issued after the change.

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