Ubuntu18.04(linux)安装MySQL

sudo apt-get --purge remove mysql-server mysql-common mysql-client
sudo apt-get install mysql-server mysql-common mysql-client

mysqladmin -u root password your-new-password
sudo /etc/init.d/mysql restart

apt-get install mariadb-server

mysql> show variables like 'char%';
+--------------------------+----------------------------+
| Variable_name            | Value                      |
+--------------------------+----------------------------+
| character_set_client     | utf8                       |
| character_set_connection | utf8                       |
| character_set_database   | latin1                     |
| character_set_filesystem | binary                     |
| character_set_results    | utf8                       |
| character_set_server     | latin1                     |
| character_set_system     | utf8                       |
| character_sets_dir       | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+

mysql> show variables like 'collation%';
+----------------------+-------------------+
| Variable_name        | Value             |
+----------------------+-------------------+
| collation_connection | utf8_general_ci   |
| collation_database   | latin1_swedish_ci |
| collation_server     | latin1_swedish_ci |
+----------------------+-------------------+

sudo vim /etc/mysql/my.cnf

[mysqld]
collation-server = utf8_unicode_ci
init-connect='SET NAMES utf8'
character-set-server = utf8

service mysql restart

ERROR 1045: Access denied for user: 'root@localhost' (Using 
password: YES)

sudo mysql -u root

SELECT User,Host FROM mysql.user;
+------------------+-----------+
| User             | Host      |
+------------------+-----------+
| admin            | localhost |
| debian-sys-maint | localhost |
| magento_user     | localhost |
| mysql.sys        | localhost |
| root             | localhost |

mysql> DROP USER 'root'@'localhost';
Query OK, 0 rows affected (0,00 sec)

mysql> CREATE USER 'root'@'%' IDENTIFIED BY '123456';
Query OK, 0 rows affected (0,00 sec)

mysql> GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' WITH GRANT OPTION;
Query OK, 0 rows affected (0,00 sec)

mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0,01 sec)

SET PASSWORD FOR root@'localhost' = PASSWORD('password');

UPDATE mysql.user SET Password=PASSWORD('newpwd') WHERE User='root';

USE mysql
UPDATE user SET Password = PASSWORD('newpwd')
WHERE Host = 'localhost' AND User = 'root';

USE mysql
UPDATE user SET Password = PASSWORD('newpwd')
WHERE Host = '%' AND User = 'root';