默认登录mysql之后show variables like ‘%character%’， 出现
mysql》 show variables like ‘%character%’;
+--------------------------+----------------------------+
| Variable_name | Value |
+--------------------------+----------------------------+
| character_set_client | latin1 |
| character_set_connection | latin1 |
| character_set_database | latin1 |
| character_set_filesystem | binary |
| character_set_results | latin1 |
| character_set_server | latin1 |
| character_set_system | utf8 |
| character_sets_dir | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+
1. 找到mysql的配置文件，拷贝到etc目录下，第一步很重要
使用find命令查找cnf文件。记得不要去找my.cnf因为它不一定存在，而应该找*.cnf。
[root@linuxserver classes] find / -iname *.cnf -print
/usr/share/doc/mysql-server-4.1.12/my-medium.cnf
/usr/share/doc/mysql-server-4.1.12/my-huge.cnf
/usr/share/doc/mysql-server-4.1.12/my-innodb-heavy-4G.cnf
/usr/share/doc/mysql-server-4.1.12/my-large.cnf
/usr/share/doc/mysql-server-4.1.12/my-small.cnf
/usr/share/texmf/web2c/mktex.cnf
/usr/share/texmf/web2c/texmf.cnf
/usr/share/texmf/web2c/fmtutil.cnf
/usr/share/texmf/tex/jadetex/jadefmtutil.cnf
/usr/share/ssl/openssl.cnf
找到之后，复制一个出来
cp /usr/share/doc/mysql-server-4.1.12/my-large.cnf /etc/my.cnf
2. 打开my.cnf修改编码
vi /etc/my.cnf
在[client]下增加default-character-set=utf8
在[mysqld]下增加default-character-set=utf8
同时加上init_connect=‘SET NAMES utf8’ (设定连接mysql数据库时使用utf8编码，以让mysql数据库为utf8运行)
重新启动mysql，执行：sudo /etc/init.d/mysql stop 然后sudo /etc/init.d/mysql start
mysql》 show variables like ‘%character%’;
+--------------------------+----------------------------+
| Variable_name | Value |
+--------------------------+----------------------------+
| character_set_client | utf8 |
| character_set_connection | utf8 |
| character_set_database | utf8 |
| character_set_filesystem | binary |
| character_set_results | utf8 |
| character_set_server | utf8 |
| character_set_system | utf8 |
| character_sets_dir | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+
即使做了以上修改如果直接数据库再创建表，然后存入中文，取出来的会是问号。解决的办法是：
创建数据库的时候指明默认字符集为utf8，如：
create database test default character set utf8;