经常会有朋友或者同事问起,MySQL的root密码忘了,不知道该怎么办,其实解决方法很简单,前面也有提起,下面是详细的操作步骤。
(1)登录到数据库所在服务器,手工kill掉MySQL进程:
kill `cat /mysql-data-directory/hostname.pid`
其中,/mysql-data-directory/hostname.pid指的是MySQL数据目录下的.pid文件,它记录了MySQL服务的进程号。(2)使用--skip-grant-tables选项重启MySQL服务:
[root@localhost mysql]# ./bin/mysqld_safe --skip-grant-tables --user=zzx &
[1] 20881
[root@localhost mysql]# Starting mysqld daemon with databases from /home/zzx/mysql/data
其中--skip-grant-tables选项前面曾经介绍过,意思是启动MySQL服务的时候跳过权限表认证。启动后,连接到MySQL的root将不需要口令。(3)用空密码的root用户连接到MySQL,并且更改root口令:
[root@localhost mysql]# mysql -uroot
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 53
Server version: 5.0.41-community-log MySQL Community Edition (GPL)
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
mysql>
mysql> set password = password('123');
ERROR 1290 (HY000): The MySQL server is running with the --skip-grant-tables option so it
cannot execute this statement
mysql> update user set password=password('123') where user='root' and host='localhost';
Query OK, 1 row affected (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 0
此时,由于使用了--skip-grant-tables选项启动,使用“set password”命令更改密码失败,直接更新user表的password字段后更改密码成功。
(4)舒心权限表,使得权限认证重新生效:
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
(5)重新用root登录时,必须输入新口令:
[root@localhost mysql]# mysql -uroot
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)
[root@localhost mysql]# mysql -uroot -p123
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 6 to server version: 5.1.11-beta-log
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
mysql>
注意:在MySQL中,密码丢失后无法找回,只能通过上述方式修改密码。