How to Change MySQL Character Set to UTF-8 on Linux

Locate the MySQL configuration file

Run a search to find any *.cnf files, for example: find / -iname "*.cnf" -print Typical locations include:

/usr/share/mysql/my-innodb-heavy-4G.cnf

/usr/share/mysql/my-large.cnf

/usr/share/mysql/my-medium.cnf

/usr/share/mysql/my-huge.cnf

/usr/share/doc/MySQL-server-community-5.1.22/my-medium.cnf

Copy a sample configuration

Choose one of the sample files (e.g., my-medium.cnf) and copy it to /etc/my.cnf:

cp /usr/share/mysql/my-medium.cnf /etc/my.cnf

Edit my.cnf to set UTF‑8

Open the file with an editor: vi /etc/my.cnf Add the following lines:

[client]
default-character-set=utf8

[mysqld]
default-character-set=utf8

Restart MySQL

Execute the service restart command: /etc/rc.d/init.d/mysql restart Then log in to verify the server is running:

mysql -u root -p

Verify the character set

Run the following queries:

show variables like 'collation_%';

show variables like 'character_set_%';

Typical output should show utf8_general_ci for collations and utf8 for all character_set variables.

Other ways to change the charset

Direct SQL commands:

use mydb;
alter database mydb character set utf8;
create database mydb character set utf8;

Modify the database option file ( /var/lib/mysql/mydb/db.opt) to replace default-character-set=latin1 with default-character-set=utf8 and restart MySQL.

Set variables at runtime:

set character_set_client=utf8;
set character_set_connection=utf8;
set character_set_database=utf8;
set character_set_results=utf8;
set character_set_server=utf8;
set collation_connection=utf8_general_ci;
set collation_database=utf8_general_ci;
set collation_server=utf8_general_ci;

After setting, verify again with the SHOW VARIABLES queries.

Background on MySQL character set defaults

MySQL determines the effective character set through a hierarchy: server defaults (compiled or set in my.cnf), character_set_server, character_set_database, table defaults, and column defaults. If none are overridden, the legacy default is latin1, but most installations configure utf8 during setup.