deepin mysql Access denied for user 'root'@'localhost'

deepin系统安装mysql出现的错误

➜  ~ mysql -uroot -p       
Enter password: 
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)

解决方法如下：

1. sudo登入mysql,修改plugin

➜  ~ sudo mysql -uroot 
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 8
Server version: 10.1.37-MariaDB-0+deb9u1 Debian 9.6

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [(none)]> UPDATE mysql.user SET plugin='mysql_native_password' WHERE User='root';
Query OK, 0 rows affected (0.00 sec)
Rows matched: 1  Changed: 0  Warnings: 0

MariaDB [(none)]> select User,Host,plugin from mysql.user;
+------+-----------+-----------------------+
| User | Host      | plugin                |
+------+-----------+-----------------------+
| root | localhost | mysql_native_password |
+------+-----------+-----------------------+
1 row in set (0.00 sec)

2. 设置密码

MariaDB [(none)]> update mysql.user set password=password('123456') where user='root';
Query OK, 1 row affected (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 0

MariaDB [(none)]> flush privileges;
Query OK, 0 rows affected (0.00 sec)

MariaDB [(none)]> quit
Bye

3. 重启mysql服务，登入。

➜  ~ sudo service mysql restart
➜  ~ mysql -uroot -p
Enter password: 
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 4
Server version: 10.1.37-MariaDB-0+deb9u1 Debian 9.6

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [(none)]>

4. Done

P.S.
但是看这个配置文件密码仍然是空，具体不了解，没有深究。有懂的求科普~

➜  ~ sudo cat /etc/mysql/debian.cnf
# Automatically generated for Debian scripts. DO NOT TOUCH!
[client]
host     = localhost
user     = root
password = 
socket   = /var/run/mysqld/mysqld.sock
[mysql_upgrade]
host     = localhost
user     = root
password = 
socket   = /var/run/mysqld/mysqld.sock
basedir  = /usr