当你在你想要更改密码的系统上使用MySQL的PASSWORD()时，它可能会导致密码在MySQL日志中以cleartext [source]显示。对我来说，让它们和备份等像密码一样安全听起来像是噩梦，所以我喜欢这样做:

On your local machine, run this with your password: mysql -u someuser -p < <(echo "SELECT PASSWORD('mypass');") Note the space in front to prevent it from turning up in the bash history (for other distros than Ubuntu, this might work differently – source). On your server machine, execute the following command to change its MySQL root password (replace myhash with your password's hash as printed by the first command): mysql -u root -p < <(echo "SET PASSWORD FOR root@localhost = 'myhash';") Optionally, let's be a bit paranoid: On your local machine, clear your terminal screen with clear and purge your virtual terminal scrollback, to hide the cleartext password appearing in the command above.

回应rogerdpack的评论:如果你不知道MySQL的根密码，并且你不关心MySQL的数据/设置，你可以重新安装它并重置根密码，如下所示:

sudo apt-get remove --purge mysql-server mysql-client mysql-common
sudo rm -rf /var/lib/mysql
sudo apt-get install -y mysql-server mysql-client 

安装过程中，您可以选择root用户的密码:

对于mysql 5.6，这个命令有效，你可以通过向导设置密码:

sudo dpkg-reconfigure mysql-server-5.6

唯一对我有效的方法是这里描述的(我运行的是ubuntu 14.04)。为了清晰起见，以下是我遵循的步骤:

sudo vim /etc/mysql/my.cnf Add the following lines at the end: [mysqld] skip-grant-tables sudo service mysql restart mysql -u root use mysql select * from mysql.user where user = 'root'; - Look at the top to determine whether the password column is called password or authentication_string UPDATE mysql.user set *password_field from above* = PASSWORD('your_new_password') where user = 'root' and host = 'localhost'; - Use the proper password column from above FLUSH PRIVILEGES; exit sudo vim /etc/mysql/my.cnf Remove the lines added in step 2 if you want to keep your security standards. sudo service mysql restart

参考:https://dev.mysql.com/doc/refman/5.7/en/resetting-permissions.html

正如mysql文档中password()函数所说:

此函数在MySQL 8.0.11中被移除。

这将使mysql v8.0.11及更新版本的所有现有答案都失效。

根据mysql文档，重置root密码的新通用方法如下:

The preceding sections provide password-resetting instructions specifically for Windows and Unix and Unix-like systems. Alternatively, on any platform, you can reset the password using the mysql client (but this approach is less secure): 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 ALTER USER and SET PASSWORD. Because this is insecure, if the server is started with the --skip-grant-tables option, it enables --skip-networking automatically to prevent remote connections. 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> ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPass'; You should now be able to connect to the MySQL server as root using the new password. Stop the server and restart it normally (without the --skip-grant-tables and --skip-networking options).

如果部署在xampp上，您可以通过提供的phpadmin gui轻松更改mysql密码。

phpMyAdmin -> User Accounts -> Edit Privileges (Select the intended user) -> Change Password (Tab)