install MariaDB 10.2 on Ubuntu 18

Here are the commands to run to install MariaDB 10.2 from the MariaDB repository on your Ubuntu system:

sudo apt-get install software-properties-common
sudo apt-key adv --recv-keys --keyserver hkp://keyserver.ubuntu.com:80 0xF1656F24C74CD1D8
sudo add-apt-repository 'deb [arch=amd64,arm64,ppc64el] http://mirrors.neusoft.edu.cn/mariadb/repo/10.2/ubuntu bionic main'

Once the key is imported and the repository added you can install MariaDB 10.2 from the MariaDB repository with:

sudo apt update
sudo apt install mariadb-server

 Some times we need to stop or start MariaDB service. Use the following commands to stop, start, check status and restart MariaDB servic.

$ sudo systemctl stop mysql.service      # To Stop MariaDB service 
$ sudo systemctl start mysql.service     # To Start MariaDB service 
$ sudo systemctl status mysql.service    # To Check MariaDB service status 
$ sudo systemctl restart mysql.service   # To Stop then Start MariaDB service 

try remotely connect to the server

it's very trick,

firstly you have to comments bind-address in file /etc/mysql/my.cnf in case you are encountering 10061 error refer to this page

#bind-address = <some ip-address>

grant user to remote access the db via root user refer to this page for details

GRANT ALL PRIVILEGES ON *.* TO 'root'@'192.168.%' IDENTIFIED BY 'my-new-password' WITH GRANT OPTION;

and then reset root user of mariadb's password  refer to this

MariaDB [(none)]> select host,user,password from mysql.user;

+-----------+------+-------------------------------------------+
| host      | user | password                                  |
+-----------+------+-------------------------------------------+
| localhost | root | *C61A1C944BC7AXXXXXXXXXXXXXX4B81A462D9CB3 |
| 127.0.0.1 | root | *C61A1C944BC7A3XXXXXXXXXXXXX4B81A462D9CB3 |
| ::1       | root | *C61A1C944BC7A3XXXXXXXXXXXXX4B81A462D9CB3 |
| %         | root | *81F5E21E35407DXXXXXXXXXXXXXEBFB6AF209E1B |   wrong password made me facing 1045 error
+-----------+------+-------------------------------------------+

restar the db service

service mysql restart

 if it's Centos 7, please use the following instead

systemctl restart mariadb.service

then connect to the db via Navicat or mariadb CLI command

mysql -h xxx.xx.xx -u root -p 

others useful command

change user password

Open the bash shell and connect to the server as root user

mysql -u root -h localhost -p

Run command:

ALTER USER admin IDENTIFIED BY 'New-Password-Here';

change databse or table charset

ALTER DATABASE databasename CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

ALTER TABLE cen_bridge_dictionary CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

 create database with specified charset

CREATE DATABASE IF NOT EXISTS RUNOOB DEFAULT CHARSET utf8mb4 COLLATE utf8mb4_unicode_ci;

backup and restore

backup db

mysqldump -u user_name -p  --databases database_name >dump.sql

restore db

mysql -u root -p[root_password] --databases database_name < dumpfilename.sql

refer to this page for charactar set

reference documents

https://askubuntu.com/questions/1009175/mariadb-10-0-33-configuring-mariadb-for-remote-client-access

https://www.jb51.net/article/26505.htm

https://mariadb.com/kb/en/library/configuring-mariadb-for-remote-client-access/

https://downloads.mariadb.org/mariadb/repositories/#mirror=neusoft&distro=Ubuntu&distro_release=bionic--ubuntu_bionic&version=10.2

https://tecadmin.net/install-mariadb-10-on-ubuntu/