MySQL改密
一、未登录mysql：
1、用初始默认密码
1 | grep password /var/log/mysqld.log |
2、更改密码
1 2 | mysqladmin -uroot -p'd-tlbwIgP3e2' password "QianFeng@123" 默认密码/老密码 新密码 |
二、已登录数据库里：
方法一
1 | set password for root@localhost = password('你要改的密码'); |
方法二
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 | mysql> select user,host,authentication_string from mysql.user;+---------------+-----------+-------------------------------------------+| user | host | authentication_string |+---------------+-----------+-------------------------------------------+| root | localhost | *1288B346EB8ABFFC6F6F1B79C437AF124FFE05C7 || mysql.session | localhost | *THISISNOTAVALIDPASSWORDTHATCANBEUSEDHERE || mysql.sys | localhost | *THISISNOTAVALIDPASSWORDTHATCANBEUSEDHERE |+---------------+-----------+-------------------------------------------+rows in set (0.00 sec)mysql> update mysql.user set -> authentication_string=password('TianYun@52') -> where user='root' and host='localhost';Query OK, 1 row affected, 1 warning (0.00 sec)Rows matched: 1 Changed: 1 Warnings: 1mysql> flush privileges;（刷新）Query OK, 0 rows affected (0.00 sec) |
方法三
1 | mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'Zjz@5740'; |
三、取消密码复杂度
vim /etc/my.cnf 配置文件里设置
1 2 3 | [mysqld]plugin-load=validate_password.sovalidate-password=OFF |
或者在数据库内执行
1 | set global validate_password.policy=0 |
作用将mysql检查密码强度降为最低，只检查密码的位数。如果你的密码强度很高，就没必要输入该条指令。
四、取消密码登录
# vim /etc/my.cnf
1 2 | [mysqld]skip-grant-tables |
注意：当skip-grant-tables和skip-network没有注销时，3306端口是不会打开的，虽然msyql running，导致navicat连接失败
#netstat -an | grep 3306
# service mysqld restart
# mysql -uroot
然后敲MySQL登录改密
# mysql -uroot
然后敲MySQL登录改密
1 2 3 | mysql> UPDATE mysql.user SET authentication_string=password('Zjz@5740') WHERE user='root' AND host='localhost';(效果最强)<br><br>mysql> FLUSH PRIVILEGES;（刷新 |
五、数据库起不来
1 2 | #chown -R mysql.mysql /var/lib/mysql (赋权)#systemctl restart mysqld |
六、mysql8版本修改密码
1、修改/etc/my.cnf配置文件
1 2 | vim /etc/my.cnf添加skip-grant-tables配置 |
2、重启mysql服务
1 | sudo systemctl restart mysqld |
3、在mysql控制台依次输入
1 2 3 4 5 | use mysql;set global validate_password.policy=0;alter user 'root'@'localhost' identified by '12345678'; |
其中set global validate_password.policy=0作用将mysql检查密码强度降为最低，只检查密码的位数。如果你的密码强度很高，就没必要输入该条指令。
上面会报错
1 2 | mysql> alter user 'root'@'localhost' identified by '12345678'; ERROR 1290 (HY000): The MySQL server is running with the --skip-grant-tables option so it cannot execute this statement |
解决：刷新一下，重新执行改密sql
1 2 3 4 5 | mysql> flush privileges;Query OK, 0 rows affected (0.01 sec)sudo systemctl restart mysqldmysql -uroot -p12345678 |
