使用SKIP-GRANT-TABLES 解决 MYSQL ROOT密码丢失（转）

Log on to your system as Administrator.

Stop the MySQL server if it is running. For a server that is running as a Windows service, go to the Services manager: From the Start menu, selectControl Panel, then Administrative Tools, then Services. Find the MySQL service in the list and stop it.

If your server is not running as a service, you may need to use the Task Manager to force it to stop.

Create a text file containing the following statement on a single line. Replace the password with the password that you want to use.

SET PASSWORD FOR 'root'@'localhost' = PASSWORD('MyNewPass');

Save the file. This example assumes that you name the file C:\mysql-init.txt.

Open a console window to get to the command prompt: From the Start menu, select Run, then enter cmd as the command to be run.

Start the MySQL server with the special --init-file option (notice that the backslash in the option value is doubled):

C:\> cd "C:\Program Files\MySQL\MySQL Server 5.0\bin"
C:\> mysqld-nt --init-file=C:\\mysql-init.txt

If you installed MySQL to a different location, adjust the cd command accordingly.

The server executes the contents of the file named by the --init-file option at startup, changing the 'root'@'localhost' account password.

To have server output to appear in the console window rather than in a log file, add the --console option to the mysqld command.

If you installed MySQL using the MySQL Installation Wizard, you may need to specify a --defaults-file option. For example:

C:\> mysqld-nt
         --defaults-file="C:\\Program Files\\MySQL\\MySQL Server 5.0\\my.ini"
         --init-file=C:\\mysql-init.txt

The appropriate --defaults-file setting can be found using the Services Manager: From the Start menu, select Control Panel, thenAdministrative Tools, then Services. Find the MySQL service in the list, right-click it, and choose the Properties option. The Path to executable field contains the --defaults-file setting.

After the server has started successfully, delete C:\mysql-init.txt.

Log on to your system as the Unix user that the MySQL server runs as (for example, mysql).

Stop the MySQL server if it is running. Locate the .pid file that contains the server's process ID. The exact location and name of this file depend on your distribution, host name, and configuration. Common locations are /var/lib/mysql/, /var/run/mysqld/, and /usr/local/mysql/data/. Generally, the file name has an extension of .pid and begins with either mysqld or your system's host name.

Stop the MySQL server by sending a normal kill (not kill -9) to the mysqld process. Use the actual path name of the .pid file in the following command:

shell> kill `cat /mysql-data-directory/host_name.pid`

Use backticks (not forward quotation marks) with the cat command. These cause the output of cat to be substituted into the kill command.

Create a text file containing the following statement on a single line. Replace the password with the password that you want to use.

SET PASSWORD FOR 'root'@'localhost' = PASSWORD('MyNewPass');

Save the file. This example assumes that you name the file /home/me/mysql-init. The file contains the password, so do not save it where it can be read by other users. If you are not logged in as mysql (the user the server runs as), make sure that the file has permissions that permit mysql to read it.

Start the MySQL server with the special --init-file option:

shell> mysqld_safe --init-file=/home/me/mysql-init &

The server executes the contents of the file named by the --init-file option at startup, changing the 'root'@'localhost' account password.

After the server has started successfully, delete /home/me/mysql-init.

Stop the MySQL server if necessary, then restart it with the --skip-grant-tables option. This enables anyone to connect without a password and with all privileges, and disables account-management statements such as SET PASSWORD. Because this is insecure, you might want to use --skip-grant-tables in conjunction with --skip-networking to prevent remote clients from connecting.

Connect to the MySQL server using the mysql client; no password is necessary because the server was started with --skip-grant-tables:

shell> mysql

In the mysql client, tell the server to reload the grant tables so that account-management statements work:

mysql> FLUSH PRIVILEGES;

Then change the 'root'@'localhost' account password. Replace the password with the password that you want to use. To change the password for a root account with a different host name part, modify the instructions to use that host name.

mysql> SET PASSWORD FOR 'root'@'localhost' = PASSWORD('MyNewPass');