1、找到my.cnf配置文件

如果/etc/目录下没有my.cnf配置文件，请到/usr/share/mysql/下找到*.cnf文件，拷贝其中一个到/etc/并改名为my.cnf)中。命令如下：

[root@test1 mysql]# cp /usr/share/mysql/my-medium.cnf　/etc/my.cnf

mysql5.5.10默认字符集修改，字符编码设置，中文乱码，gb2312，gbk，utf8格式存储数据

通过修改mysql默认字符集，可以存储中文数据，以免出现中文乱码，以下以设置为utf8为例。

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以下内容是在本机安装的mysql-5.5.10上,没有修改my.ini前显示结果
===================================================================================

 mysql> show variables like 'character%';
+--------------------------+---------------------------------+
| Variable_name            | Value                           |
+--------------------------+---------------------------------+
| character_set_client     | gbk                             |
| character_set_connection | gbk                             |
| character_set_database   | latin1                          |
| character_set_filesystem | binary                          |
| character_set_results    | gbk                             |
| character_set_server     | latin1                          |
| character_set_system     | utf8                            |
| character_sets_dir       |/usr/share/mysql/charsets/ |
+--------------------------+---------------------------------+
8 rows in set (0.02 sec)

mysql> show variables like 'collation%';
+----------------------+-------------------+
| Variable_name        | Value             |
+----------------------+-------------------+
| collation_connection | gbk_chinese_ci    |
| collation_database   | latin1_swedish_ci |
| collation_server     | latin1_swedish_ci |
+----------------------+-------------------+
3 rows in set (0.00 sec)

==============================================================================

关闭mysql服务，在mysql安装目录下，my.ini文件进行如下修改，没有则直接进行添加
==============================================================================

[client]
#修改客户端默认字符编码格式为utf8
default-character-set=utf8
[mysqld]
#修改服务器端默认字符编码格式为utf8
character-set-server = utf8

=============================================================================

修改后，再次输入命令查看，显示结果如下
==============================================================================

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)

mysql> show variables like 'collation%';
+----------------------+-----------------+
| Variable_name        | Value           |
+----------------------+-----------------+
| collation_connection | utf8_general_ci |
| collation_database   | utf8_general_ci |
| collation_server     | utf8_general_ci |
+----------------------+-----------------+
3 rows in set (0.00 sec)

================================================================================

查看mysql已经安装的所有字符集，也就是在mysql中可以使用的字符集，结果如下
================================================================================

mysql> show character set;
+----------+-----------------------------+---------------------+--------+
| Charset  | Description                 | Default collation   | Maxlen |
+----------+-----------------------------+---------------------+--------+
| big5     | Big5 Traditional Chinese    | big5_chinese_ci     |      2 |
| dec8     | DEC West European           | dec8_swedish_ci     |      1 |
| cp850    | DOS West European           | cp850_general_ci    |      1 |
| hp8      | HP West European            | hp8_english_ci      |      1 |
| koi8r    | KOI8-R Relcom Russian       | koi8r_general_ci    |      1 |
| latin1   | cp1252 West European        | latin1_swedish_ci   |      1 |
| latin2   | ISO 8859-2 Central European | latin2_general_ci   |      1 |
| swe7     | 7bit Swedish                | swe7_swedish_ci     |      1 |
| ascii    | US ASCII                    | ascii_general_ci    |      1 |
| ujis     | EUC-JP Japanese             | ujis_japanese_ci    |      3 |
| sjis     | Shift-JIS Japanese          | sjis_japanese_ci    |      2 |
| hebrew   | ISO 8859-8 Hebrew           | hebrew_general_ci   |      1 |
| tis620   | TIS620 Thai                 | tis620_thai_ci      |      1 |
| euckr    | EUC-KR Korean               | euckr_korean_ci     |      2 |
| koi8u    | KOI8-U Ukrainian            | koi8u_general_ci    |      1 |
| gb2312   | GB2312 Simplified Chinese   | gb2312_chinese_ci   |      2 |
| greek    | ISO 8859-7 Greek            | greek_general_ci    |      1 |
| cp1250   | Windows Central European    | cp1250_general_ci   |      1 |
| gbk      | GBK Simplified Chinese      | gbk_chinese_ci      |      2 |
| latin5   | ISO 8859-9 Turkish          | latin5_turkish_ci   |      1 |
| armscii8 | ARMSCII-8 Armenian          | armscii8_general_ci |      1 |
| utf8     | UTF-8 Unicode               | utf8_general_ci     |      3 |
| ucs2     | UCS-2 Unicode               | ucs2_general_ci     |      2 |
| cp866    | DOS Russian                 | cp866_general_ci    |      1 |
| keybcs2  | DOS Kamenicky Czech-Slovak  | keybcs2_general_ci  |      1 |
| macce    | Mac Central European        | macce_general_ci    |      1 |
| macroman | Mac West European           | macroman_general_ci |      1 |
| cp852    | DOS Central European        | cp852_general_ci    |      1 |
| latin7   | ISO 8859-13 Baltic          | latin7_general_ci   |      1 |
| utf8mb4  | UTF-8 Unicode               | utf8mb4_general_ci  |      4 |
| cp1251   | Windows Cyrillic            | cp1251_general_ci   |      1 |
| utf16    | UTF-16 Unicode              | utf16_general_ci    |      4 |
| cp1256   | Windows Arabic              | cp1256_general_ci   |      1 |
| cp1257   | Windows Baltic              | cp1257_general_ci   |      1 |
| utf32    | UTF-32 Unicode              | utf32_general_ci    |      4 |
| binary   | Binary pseudo charset       | binary              |      1 |
| geostd8  | GEOSTD8 Georgian            | geostd8_general_ci  |      1 |
| cp932    | SJIS for Windows Japanese   | cp932_japanese_ci   |      2 |
| eucjpms  | UJIS for Windows Japanese   | eucjpms_japanese_ci |      3 |
+----------+-----------------------------+---------------------+--------+
39 rows in set (0.00 sec)

===============================================================================

经过所有以上设置以后，mysql中所有字符集都是utf8的了，但是在控制台操作的时候，还是会出现乱码中文乱码。
这是因为windows XP的控制台窗口默认显示字符编码格式为gbk，所以这里要设置显示结果使用的字符编码格式为utf8。
每次在控制台进行操作的时候，都要进行如下这个设置，结果才能正常显示中文
===============================================================================

mysql> set character_set_results='gbk';
Query OK, 0 rows affected (0.00 sec)

===============================================================================

一般就算设置了表的默认字符集为utf8并且通过UTF-8编码发送查询，你会发现存入数据库的仍然是乱码。
问题就出在这个connection连接层上。解决方法是在发送查询前执行一下下面这句：
===============================================================================

mysql> set names gbk;
Query OK, 0 rows affected (0.00 sec)

它相当于下面的三句指令：

SET character_set_client = utf8;

SET character_set_results = utf8;

SET character_set_connection = utf8;
因此，这个方法也可以解决所有字符编码设置为utf8，而控制台显示中文乱码的问题。