MySQL修改root密码
MySQL修改root密码
- 方法一
- 方法二
- 方法三（此方法在MySQL8.0后失效，后期具体更改root密码查看官网的官方文档）
- 方法四
- 遗忘root密码
下方全部演示均是在不同虚拟机完成
方法一
[root@localhost ~]# mysqladmin -uroot -p"*+/.j9AB).SR" password //冒号中为原始密码
mysqladmin: [Warning] Using a password on the command line interface can be insecure.
New password: //输入新密码，此处写的是MySql@123
Confirm new password: //确认新密码（再次输入新密码），此处写的是MySql@123
Warning: Since password will be sent to server in plain text, use ssl connection to ensure password safety.
//测试登录
[root@localhost ~]# mysql -uroot -pMySql@123 //一般不建议此种写法，容易泄露密码，此处仅为了演示
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 6
Server version: 5.7.37 MySQL Community Server (GPL)
Copyright (c) 2000, 2022, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
//登录成功
方法二
mysql> ALTER USER root@localhost identified by 'MySql@123'; //进入MySQL后进行配置，末尾“MySql@123”为密码
Query OK, 0 rows affected (0.00 sec)
mysql> quit
Bye
//测试登录
[root@localhost ~]# mysql -uroot -pMySql@123 //一般不建议此种写法，容易泄露密码，此处仅为了演示
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 7
Server version: 5.7.37 MySQL Community Server (GPL)
Copyright (c) 2000, 2022, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
//登录成功
方法三（此方法在MySQL8.0后失效，后期具体更改root密码查看官网的官方文档）
mysql> select user,host,authentication_string from mysql.user; //查看用户密码对应
+---------------+-----------+-------------------------------------------+
| user | host | authentication_string |
+---------------+-----------+-------------------------------------------+
| root | localhost | *6311658AA054458F319CF5563D0E486799BB2871 |
| mysql.session | localhost | *THISISNOTAVALIDPASSWORDTHATCANBEUSEDHERE |
| mysql.sys | localhost | *THISISNOTAVALIDPASSWORDTHATCANBEUSEDHERE |
+---------------+-----------+-------------------------------------------+
3 rows in set (0.00 sec)
mysql> update mysql.user set authentication_string=password('MySql@123')
-> where user='root' and host='localhost';
Query OK, 1 row affected, 1 warning (0.05 sec)
Rows matched: 1 Changed: 1 Warnings: 1
//通过update命令更新密码
mysql> flush privileges; //刷新权限，这一步极其重要，不刷新权限无法登录
Query OK, 0 rows affected (0.00 sec)
mysql> \q
Bye
//测试登录
[root@localhost ~]# mysql -uroot -pMySql@123 //一般不建议此种写法，容易泄露密码，此处仅为了演示
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.37 MySQL Community Server (GPL)
Copyright (c) 2000, 2022, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
//登录成功
方法四
mysql> set password for root@localhost = password('MySql@123'); //进入MySQL后进行配置，末尾“MySql@123”为密码
Query OK, 0 rows affected, 1 warning (0.00 sec)
//测试登录
[root@localhost ~]# mysql -uroot -pMySql@123 //一般不建议此种写法，容易泄露密码，此处仅为了演示
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.7.37 MySQL Community Server (GPL)
Copyright (c) 2000, 2022, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
//登录成功
遗忘root密码
[root@localhost ~]# systemctl stop mysqld //关闭MySQL服务
[root@localhost ~]# vim /etc/my.cnf //修改MySQL主配置文件
[root@localhost ~]# cat /etc/my.cnf //查看MySQL主配置文件修改内容（往[mysqld]末尾添加skip-grant-tables语句，进行免密登录）
# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html
[mysqld]
#
# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
# innodb_buffer_pool_size = 128M
#
# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin
#
# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
skip-grant-tables //末尾加上此条语句，进行免密登录MySQL
[root@localhost ~]# systemctl start mysqld //重新启动MySQL服务
[root@localhost ~]# mysql -uroot //免密登录
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.37 MySQL Community Server (GPL)
Copyright (c) 2000, 2022, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
//修改密码
mysql> update mysql.user set authentication_string=password('MySql@123')
-> where user='root' and host='localhost';
Query OK, 0 rows affected, 1 warning (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 1
mysql> flush privileges; //记得刷新权限，不然无法登录
Query OK, 0 rows affected (0.00 sec)
mysql> \q
Bye
//测试登录
[root@localhost ~]# mysql -uroot -pMySql@123 //一般不建议此种写法，容易泄露密码，此处仅为了演示
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.7.37 MySQL Community Server (GPL)
Copyright (c) 2000, 2022, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
//登录成功
//注：最后记得把主配置文件中的免密登录语句删掉，事先关闭MySQL服务，删掉语句后再重启MySQL服务