[mysql]root用户登录mysql,输入密码后报错:Access denied for user 'root'@'localhost'

问题如下:

wangju@wangju-HP-348-G4:~$ mysql -u root -p
Enter password:
ERROR 1698 (28000): Access denied for user 'root'@'localhost'

 解决办法: 分2步

• 配置mysql不用密码也能登录
• 重新配置mysql用户名密码

首先:配置mysql不用密码也能登录

step1:

使用find全局搜索mysql配置文件

root@wangju-HP-348-G4:/home/wangju# find / -name mysqld.cnf
/etc/mysql/mysql.conf.d/mysqld.cnf

step2:

在mysql的配置文件[mysqld]中加入下面这句话:

skip-grant-tables　　　　<-- add here

作用：就是让你可以不用密码登录进去mysql。

step3:

保存修改,重新启动mysql

service mysql restart

step4:

在终端上输入mysql -u root -p，遇见输入密码的提示直接回车即可进入mysql

然后:重新配置mysql用户名密码
step1:
进入mysql后分别执行下面三句话配置root用户密码

use mysql;   然后敲回车

update user set authentication_string=password("你的密码") where user="root";  然后敲回车

flush privileges;  然后敲回车

结果如下:

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 user set authentication_string=password("admin123456") where user="root";
Query OK, 1 row affected, 1 warning (0.02 sec)
Rows matched: 2  Changed: 1  Warnings: 1

mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)

然后输入quit，退出mysql。

step2：

重新进入到mysqld.cnf文件中去把刚开始加的skip-grant-tables这条语句给注释掉。

再返回终端输入mysql -u root -p，报错:

root@wangju-HP-348-G4:/home/wangju# mysql -u root -p
Enter password:
ERROR 1524 (HY000): Plugin 'auth_socket' is not loaded

再把刚才注释掉的skip-external-locking取消注释,然后重启mysql

执行下面的命令:

use mysql;
#切换数据库

select user,plugin from user;
#查询user表 user列,plugin列的值
#从查询结果可以看出plugin root的字段是auth_socket，把它改为mysql_native_password

update user set authentication_string=password("admin123456"),plugin='mysql_native_password' where user='root';
#更新user表plugin root

执行结果:

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> select user,plugin from user;
+------------------+-----------------------+
| user             | plugin                |
+------------------+-----------------------+
| root             | auth_socket           |
| mysql.session    | mysql_native_password |
| mysql.sys        | mysql_native_password |
| debian-sys-maint | mysql_native_password |
| root             | mysql_native_password |
| tester           | mysql_native_password |
+------------------+-----------------------+
6 rows in set (0.00 sec)

mysql> update user set authentication_string=password("admin123456"),plugin='mysql_native_password' where user='root';
Query OK, 1 row affected, 1 warning (0.00 sec)
Rows matched: 2  Changed: 1  Warnings: 1

再输入select user,plugin from user;回车，我们能看到root用户的字段改成功了。

mysql> select user,plugin from user;
+------------------+-----------------------+
| user             | plugin                |
+------------------+-----------------------+
| root             | mysql_native_password |
| mysql.session    | mysql_native_password |
| mysql.sys        | mysql_native_password |
| debian-sys-maint | mysql_native_password |
| root             | mysql_native_password |
| tester           | mysql_native_password |
+------------------+-----------------------+
6 rows in set (0.00 sec)

step3:

quit退出,再执行step3,重启mysql

结果:

再用mysql -u root -p,回车,输入密码之后,就可以登录成功了

参考文档:

mysql出现ERROR1698(28000):Access denied for user root@localhost错误解决方法