安装了个5.5版本的mysql，字符集出现了问题，之前的mysql服务器都是通过在my.cnf配置文件中进行配置便可，可是今儿怎么着都不行一直报错：
当时系统中也没有配置错误日志，所以只能是先配置下错误日志的位置，看看到底是哪里出错了：
user = mysql
pid-file = /var/run/mysqld/mysqld.pid
socket = /var/run/mysqld/mysqld.sock
port = 3306
basedir = /usr
datadir = /var/lib/mysql
tmpdir = /tmp
log-error=/var/log/mysql/error.log
lc-messages-dir = /usr/share/mysql
skip-external-locking
default-character-set=utf8
结果查看了错误日志才发现是字符集的错误：
[ERROR] /usr/sbin/mysqld: unknown variable 'default-character-set=utf8'
居然不认识，上网上了找了下发现也有人遇到了，说是5.5中mysql不再使用default-character-set这种写法了。
具体请看：http://dev.mysql.com/doc/refman/5.5/en/server-options.html#option_mysqld_default-character-set
把default-character-set=utf8 改成： character-set-server=utf8就可以了。
root@chenDBA:/etc/mysql# vim my.cnf
root@chenDBA:/etc/mysql# service mysql start
mysql start/running, process 5904
root@chenDBA:/etc/mysql# mysql -uroot -p
Enter password:
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/ |
+--------------------------+----------------------------+
8 rows in set (0.00 sec)
OK收工了。