解決mysql ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)

一、問題描述

因爲誤用快捷鍵導致mysql退出，再次登錄時顯示錯誤：ERROR 1045 (28000): Access denied for user ‘root’@‘localhost’ (using password: YES)

二、問題解決過程

1.打開/etc/mysql/mysql.conf.d/mysqld.cnf 文件,命令如下

$ sudo vi /etc/mysql/mysql.conf.d/mysqld.cnf

2.找到[mysqld]段，並加入一行“skip-grant-tables”

3.重啓mysql服務,用空密碼進入mysql管理命令行，切換到mysql庫,操作命令如下，

$ mysql
Welcome to the MySQL monitor. Commands end with ; or \g. 
mysql> use mysql
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> update mysql.user set authentication_string=password('newpass') where user='root' and Host ='localhost';
Query OK, 1 row affected, 1 warning (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 1
mysql> update user set plugin="mysql_native_password"; 
Query OK, 0 rows affected (0.00 sec)
Rows matched: 3 Changed: 0 Warnings: 0
mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)
mysql> quit;
Bye

4.回到sudo vi /etc/mysql/mysql.conf.d/mysqld.cnf，把剛纔加入的那一行“skip-grant-tables”註釋或刪除掉。

5.再次重啓mysql服務sudo service mysql restart，使用新的密碼登陸，修改成功。

$ mysql -u root -p new_pass 
Welcome to the MySQL monitor. Commands end with ; or \g. 
mysql>