mysql user password modification

MySQL database is a relational database management system commonly used to manage and store large amounts of structured data. In daily database management, a common problem is to change the user password of the MySQL database. This article will introduce how to change user passwords in MySQL, as well as some things you should pay attention to during the modification process.

Part One: Preparation

Before changing the MySQL user password, some preparations need to be done to ensure that all operations proceed smoothly. Specifically, it includes the following steps:

1. Log in to the MySQL database

Before performing any database operations, you must first log in to the MySQL database. You can enter the following command on the command line to log in:

mysql -u 用户名 -p

where the username is the username of a user that already exists in the MySQL database. After entering this command, MySQL will prompt you for the user's password.

2. Select the target database

After successful login, you need to first select the target database for which you want to modify the user password. You can use the following command in the MySQL command line to select the database:

use 目标数据库名称;

Before modifying the user password, you must select the target database to be modified.

Part 2: Modify user password

Modifying the MySQL user password usually requires executing the following two SQL commands: UPDATE and FLUSH PRIVILEGES. The following is a detailed introduction to these two commands and how to use them.

1. Use the UPDATE command

In the MySQL database, you can use the SQL command UPDATE to modify the user password. The specific command format is as follows:

UPDATE mysql.user SET Password=PASSWORD('新密码') WHERE User='用户名';

Among them, "mysql.user" represents the user information table, which should be set to the correct location where the user table is located. If you are unsure of the table host, view the following information on the MySQL command line:

SHOW VARIABLES LIKE 'basedir';
SHOW VARIABLES LIKE 'datadir';

This will display the installation location and data file location of the MySQL server. Under these locations you should be able to find the mysql.user table.

"Password" represents the password column, "Password" is used to set a new password, and "Username" is the username of the user who wants to change the password.

For example, if you want to change the password of user "example" to "newpassword", the command line should be written like this:

UPDATE mysql.user SET Password=PASSWORD('newpassword') WHERE User='example';

After executing this command, the MySQL server will not synchronize this immediately Change. Instead, you need to use the FLUSH PRIVILEGES command to reload the access table and make it effective immediately.

2. Use the FLUSH PRIVILEGES command

FLUSH PRIVILEGES is a MySQL command that can reload the access permission table to make the new user password settings take effect.

The specific command is as follows:

FLUSH PRIVILEGES;

This command must be executed before all users operate the server.

Part 3: Precautions for changing passwords

When changing the MySQL user password, you need to pay attention to the following issues:

1. You must have sufficient permissions

Before changing the MySQL user password, you must have sufficient permissions. Generally, only the root user has the authority to change the passwords of other users. Otherwise, MySQL returns an insufficient permissions error message.

2. The new password should be a strong password

When you set a new password, you should make sure it is strong enough. A strong password should be long enough and include a variety of characters such as letters, numbers, and symbols. This ensures that passwords are harder to guess and protects the data in the database.

3. The access permission table needs to be reloaded in time

After the MySQL user password is modified, the access permission table needs to be reloaded in time for the change to take effect. If you don't reload this table, access permissions may become corrupted and old passwords may remain in effect.

Conclusion:

Changing the MySQL user password is relatively simple. You only need to use the two MySQL commands UPDATE and FLUSH PRIVILEGES to complete. However, there are some details that need to be paid attention to when operating to ensure that the changes take effect and protect the database from potential security threats. I hope this article can help you complete the task of changing the MySQL user password.

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