MySQL忘记密码

1、编辑MySQL配置文件

sudo vim /etc/my.cnf

2、在配置文件中的[mysqld]下加入skip-grant-tables

# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/8.0/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 the leading "# " to disable binary logging
# Binary logging captures changes between backups and is enabled by
# default. It's default setting is log_bin=binlog
# disable_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
#
# Remove leading # to revert to previous value for default_authentication_plugin,
# this will increase compatibility with older clients. For background, see:
# https://dev.mysql.com/doc/refman/8.0/en/server-system-variables.html#sysvar_default_authentication_plugin
# default-authentication-plugin=mysql_native_password

datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock

log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

skip-grant-tables

3、重启MySQL服务

sudo systemctl restart mysqld

4、进入MySQL

sudo mysql

5、刷新权限

FLUSH PRIVILEGES;

6、修改密码

select user,host from mysql.user where user = 'root';

-- 如果查询结果host的值为 localhost 执行
ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'Lihaozhe!!@@6633';

-- 如果查询结果host的值为 % 执行
ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY 'Lihaozhe!!@@6633';

-- 如果遇到 ERROR 1290 (HY000): The MySQL server is running with the --skip-grant-tables option so it cannot execute this statement
-- 先执行 FLUSH PRIVILEGES; 再修改密码

-- 如果遇到 ERROR 1227 (42000): Access denied; you need (at least one of) the SYSTEM_USER privilege(s) for this operation
-- 原因是由于root用户没有SYSTEM_USER权限，把权限加入后即可解决：
grant system_user on *.* to 'root';

7、刷新权限

FLUSH PRIVILEGES;

8、退出MySQL

exit;

9、编辑MySQL配置文件

sudo vim /etc/my.cnf

10、在配置文件中注释 skip-grant-tables

# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/8.0/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 the leading "# " to disable binary logging
# Binary logging captures changes between backups and is enabled by
# default. It's default setting is log_bin=binlog
# disable_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
#
# Remove leading # to revert to previous value for default_authentication_plugin,
# this will increase compatibility with older clients. For background, see:
# https://dev.mysql.com/doc/refman/8.0/en/server-system-variables.html#sysvar_default_authentication_plugin
# default-authentication-plugin=mysql_native_password

datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock

log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

# skip-grant-tables