需求描述：
mysql数据库支持很多字符集，那么如何查看当前的mysql版本中支持的或者说可用的字符集有什么呢？
操作过程：
1.使用show character set的方式获取当前版本中支持的字符集
mysql> select version(); #查看当前的数据库版本。
+------------+
| version() |
+------------+
| 5.5.57-log |
+------------+
1 row in set (0.00 sec) 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) mysql> #当前数据库共计支持39个字符集。
备注：通过show character set；方式查出来的是当前所有可用的字符集。
2.通过like方式过滤某个特定字符集的信息(查看数据库中是否支持某个特定的字符集)
mysql> show character set like '%latin%'; #即如果要直接查看某个特定字符集是否存在，就可以用这种方式。
+---------+-----------------------------+-------------------+--------+
| Charset | Description | Default collation | Maxlen |
+---------+-----------------------------+-------------------+--------+
| latin1 | cp1252 West European | latin1_swedish_ci | 1 |
| latin2 | ISO 8859-2 Central European | latin2_general_ci | 1 |
| latin5 | ISO 8859-9 Turkish | latin5_turkish_ci | 1 |
| latin7 | ISO 8859-13 Baltic | latin7_general_ci | 1 |
+---------+-----------------------------+-------------------+--------+
4 rows in set (0.00 sec)
或者通过where的方式过滤某个特定的字符集
mysql> show character set where charset = 'latin1';
+---------+----------------------+-------------------+--------+
| Charset | Description | Default collation | Maxlen |
+---------+----------------------+-------------------+--------+
| latin1 | cp1252 West European | latin1_swedish_ci | 1 |
+---------+----------------------+-------------------+--------+
1 row in set (0.00 sec) mysql> show character set where charset like 'latin1';
+---------+----------------------+-------------------+--------+
| Charset | Description | Default collation | Maxlen |
+---------+----------------------+-------------------+--------+
| latin1 | cp1252 West European | latin1_swedish_ci | 1 |
+---------+----------------------+-------------------+--------+
1 row in set (0.00 sec) mysql> show character set where charset like '%latin%';
+---------+-----------------------------+-------------------+--------+
| Charset | Description | Default collation | Maxlen |
+---------+-----------------------------+-------------------+--------+
| latin1 | cp1252 West European | latin1_swedish_ci | 1 |
| latin2 | ISO 8859-2 Central European | latin2_general_ci | 1 |
| latin5 | ISO 8859-9 Turkish | latin5_turkish_ci | 1 |
| latin7 | ISO 8859-13 Baltic | latin7_general_ci | 1 |
+---------+-----------------------------+-------------------+--------+
4 rows in set (0.00 sec)
3.通过查看information_schema数据库下character_sets表
mysql> desc information_schema.character_sets;
+----------------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------------+-------------+------+-----+---------+-------+
| CHARACTER_SET_NAME | varchar(32) | NO | | | |
| DEFAULT_COLLATE_NAME | varchar(32) | NO | | | |
| DESCRIPTION | varchar(60) | NO | | | |
| MAXLEN | bigint(3) | NO | | 0 | |
+----------------------+-------------+------+-----+---------+-------+
4 rows in set (0.00 sec) mysql> select character_set_name,default_collate_name,description,maxlen from information_schema.character_sets;
+--------------------+----------------------+-----------------------------+--------+
| character_set_name | default_collate_name | description | maxlen |
+--------------------+----------------------+-----------------------------+--------+
| big5 | big5_chinese_ci | Big5 Traditional Chinese | 2 |
| dec8 | dec8_swedish_ci | DEC West European | 1 |
| cp850 | cp850_general_ci | DOS West European | 1 |
| hp8 | hp8_english_ci | HP West European | 1 |
| koi8r | koi8r_general_ci | KOI8-R Relcom Russian | 1 |
| latin1 | latin1_swedish_ci | cp1252 West European | 1 |
| latin2 | latin2_general_ci | ISO 8859-2 Central European | 1 |
| swe7 | swe7_swedish_ci | 7bit Swedish | 1 |
| ascii | ascii_general_ci | US ASCII | 1 |
| ujis | ujis_japanese_ci | EUC-JP Japanese | 3 |
| sjis | sjis_japanese_ci | Shift-JIS Japanese | 2 |
| hebrew | hebrew_general_ci | ISO 8859-8 Hebrew | 1 |
| tis620 | tis620_thai_ci | TIS620 Thai | 1 |
| euckr | euckr_korean_ci | EUC-KR Korean | 2 |
| koi8u | koi8u_general_ci | KOI8-U Ukrainian | 1 |
| gb2312 | gb2312_chinese_ci | GB2312 Simplified Chinese | 2 |
| greek | greek_general_ci | ISO 8859-7 Greek | 1 |
| cp1250 | cp1250_general_ci | Windows Central European | 1 |
| gbk | gbk_chinese_ci | GBK Simplified Chinese | 2 |
| latin5 | latin5_turkish_ci | ISO 8859-9 Turkish | 1 |
| armscii8 | armscii8_general_ci | ARMSCII-8 Armenian | 1 |
| utf8 | utf8_general_ci | UTF-8 Unicode | 3 |
| ucs2 | ucs2_general_ci | UCS-2 Unicode | 2 |
| cp866 | cp866_general_ci | DOS Russian | 1 |
| keybcs2 | keybcs2_general_ci | DOS Kamenicky Czech-Slovak | 1 |
| macce | macce_general_ci | Mac Central European | 1 |
| macroman | macroman_general_ci | Mac West European | 1 |
| cp852 | cp852_general_ci | DOS Central European | 1 |
| latin7 | latin7_general_ci | ISO 8859-13 Baltic | 1 |
| utf8mb4 | utf8mb4_general_ci | UTF-8 Unicode | 4 |
| cp1251 | cp1251_general_ci | Windows Cyrillic | 1 |
| utf16 | utf16_general_ci | UTF-16 Unicode | 4 |
| cp1256 | cp1256_general_ci | Windows Arabic | 1 |
| cp1257 | cp1257_general_ci | Windows Baltic | 1 |
| utf32 | utf32_general_ci | UTF-32 Unicode | 4 |
| binary | binary | Binary pseudo charset | 1 |
| geostd8 | geostd8_general_ci | GEOSTD8 Georgian | 1 |
| cp932 | cp932_japanese_ci | SJIS for Windows Japanese | 2 |
| eucjpms | eucjpms_japanese_ci | UJIS for Windows Japanese | 3 |
+--------------------+----------------------+-----------------------------+--------+
39 rows in set (0.00 sec)
备注：字段default_collate_name是当前字符集默认的collation的名字。
文档创建时间：2018年3月28日16:41:01