How to Fully Uninstall, Install, and Configure MySQL Character Set on Linux

Preface

Installing and configuring MySQL on Linux is common, but many tutorials miss proper character set setup; this guide shares a hands‑on solution.

Complete MySQL removal

Check if MySQL is installed: ps -aux|grep mysql If installed, purge it with three commands:

sudo apt-get autoremove --purge mysql-server-5.5
sudo apt-get remove mysql-common
dpkg -l | grep ^rc | awk '{print $2}' | sudo xargs dpkg -P

Be sure of your MySQL version before running.

MySQL installation

sudo apt-get install mysql-server
sudo apt-get install mysql-client

Configuring MySQL character set

Open MySQL: mysql -uroot -p Check current character set variables: show variables like '%character%'; The result shows character_set_database and character_set_server are not set to UTF‑8.

Edit the configuration file: sudo vim /etc/mysql/my.cnf Or use gedit if vim is unavailable: sudo gedit /etc/mysql/my.cnf For MySQL 5.5 and below:

[client]
default-character-set = utf8
[mysqld]
default-character-set = utf8

For MySQL 5.5 and above:

[client]
default-character-set = utf8
[mysqld]
character-set-server = utf8

Restart MySQL (choose one): sudo /etc/init.d/mysql restart or

sudo service mysql restart

After restart, verify the character set; all databases except system should now use UTF‑8.

Note

Databases created before changing the character set may contain garbled Chinese characters; back up the data and recreate the databases after the configuration change.