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How to delete mysql user

青灯夜游

Dec 31, 2021 pm 02:54 PM

mysqldelete users

Delete method: 1. Use the "DROP USER" statement, the syntax "DROP USER 'username';"; 2. Use the DELETE statement, the syntax "DELETE FROM mysql.user WHERE Host='hostname' AND User='username';".

How to delete mysql user

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

In the MySQL database, you can use the DROP USER statement to delete users, or you can directly delete users and related permissions in the mysql.user table.

1. Use the DROP USER statement to delete ordinary users

The syntax format of using the DROP USER statement to delete users is as follows:

DROP USER <用户1> [ , <用户2> ]…

Among them, the user uses Specify the user account to be deleted.

The following points should be noted when using the DROP USER statement:

The DROP USER statement can be used to delete one or more users and revoke their permissions.
To use the DROP USER statement, you must have the DELETE permission of the mysql database or the global CREATE USER permission.
In the use of the DROP USER statement, if the host name of the account is not explicitly given, the host name defaults to "%".

Note: A user's deletion will not affect tables, indexes, or other database objects they previously created, because MySQL does not record who created these objects.

Example 1

The following uses the DROP USER statement to delete user 'test1@'localhost'. The SQL statement and execution process are as follows.

mysql> DROP USER &#39;test1&#39;@&#39;localhost&#39;;
Query OK, 0 rows affected (0.00 sec)

In the cmd command line tool, use the test1 user to log in to the database server. It is found that the login fails, indicating that the user has been deleted, as shown below.

C:\Users\USER>mysql -h localhost -u test1 -p
Enter password: ****
ERROR 1045 (28000): Access denied for user &#39;test&#39;@&#39;localhost&#39; (using  password: YES)

2. Use the DELETE statement to delete ordinary users

You can use the DELETE statement to directly delete the corresponding user information in the mysql.user table, but you must own the mysql.user table DELETE permission. Its basic syntax format is as follows:

DELETE FROM mysql.user WHERE Host=&#39;hostname&#39; AND User=&#39;username&#39;;

Both fields Host and User are the primary keys of the mysql.user table. Therefore, values from both fields are required to identify a record.

Example 2

The following uses the DELETE statement to delete user 'test2'@'localhost'. The SQL statement and execution process are shown below.

DELETE FROM mysql.user WHERE Host=&#39;localhost&#39;AND User=&#39;test2&#39;;
Query OK, 1 rows affected (0.00 sec)

The result shows that the deletion was successful. You can use a SELETE statement to query the mysql.user table to determine whether the user has been successfully deleted.

[Related recommendations: mysql video tutorial]

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