方法一：通用方法--启动时跳过权限表
1> 停止数据库
以管理员方式打开cmd！！
C:\Users\Administrator>net stop mysql
MySQL 服务正在停止..
MySQL 服务已成功停止。
2> 启动时跳过权限表
mysqld --console --skip-grant-tables --shared-memory
C:\Users\Administrator>mysqld --console --skip-grant-tables --shared-memory
注意：不要关闭终端
3> 重开新的终端（再开一个终端），登录并设置新密码
PS C:\Users\Administrator> mysql -uroot -p
Enter password: 直接敲回车键
mysql> flush privileges;
mysql> alter user root@localhost identified by '123456'; //重置密码
4> 退出MySQL，关闭第一个终端，正常启动服务。
mysql> \q
PS C:\Users\Administrator> net start mysql
MySQL 服务正在启动 ..
MySQL 服务已经启动成功。
PS C:\Users\Administrator> mysql -uroot -p123456
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 8
Server version: 8.0.36 MySQL Community Server - GPL
Copyright (c) 2000, 2024, 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> \q
Bye
方法二：参考官方文档
1> 停止服务
PS C:\Users\Administrator> net stop mysql
MySQL 服务正在停止.
MySQL 服务已成功停止。
2> 创建一个文本文件到mysql文件夹里，保存为 mysql_init.txt ，内容如下：
ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';
3> 启动同时使用上一步文件修改密码
要求管理员身份打开cmd来运行命令，暂时不要关闭终端：
C:\Users\Administrator>mysqld --init-file= F:\mysql\mysql-8.0.36-winx64\mysql_init.txt
（具体路径复制粘贴）
4> 打开另一个终端，登录测试
PS C:\Users\Administrator> mysql -uroot -p123456
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 9
Server version: 8.0.36 MySQL Community Server - GPL
Copyright (c) 2000, 2024, 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> \q
Bye
5> 关闭第一个终端，正常启动服务。
C:\Users\Administrator>net start mysql
MySQL 服务正在启动 ..
MySQL 服务已经启动成功。
C:\Users\Administrator>mysql -uroot -p123456
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 8
Server version: 8.0.36 MySQL Community Server - GPL
Copyright (c) 2000, 2024, 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> \q
Bye