一、查看字符集

1.查看MYSQL数据库服务器和数据库字符集

方法一：show variables like '%character%';

方法二：show variables like 'collation%';

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/local/mysql5535/share/charsets/ |
+--------------------------+--------------------------------------+
8 rows in set (0.00 sec)

方法一：

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)

方法二：

2.查看MYSQL所支持的字符集

show charset;

mysql> show charset;
+----------+-----------------------------+---------------------+--------+
| 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)

查看MYSQL所支持的字符集

3.查看库的字符集

语法：show database status from 库名 like  表名;

mysql> show create database shiyan\G
*************************** 1. row ***************************
  Database: shiyan
Create Database: CREATE DATABASE `shiyan` /*!40100 DEFAULT CHARACTER SET gbk */
1 row in set (0.00 sec)

4.查看表的字符集

语法：show table status from 库名 like  表名;

mysql> show table status from class_7 like 'test_info';

mysql> show table status from class_7 like 'test_info';
+-----------+--------+---------+------------+------+----------------+-------------------------+-------------+------------+-----------------+----------+-
| Name  | Engine | Version | Row_format | Rows | Avg_row_length | Data_leate_time   | Update_time | Check_time | Collation  | Checksum | 
+-----------+--------+---------+------------+------+----------------+-------------------------+-------------+------------+-----------------+----------+-
| test_info | InnoDB |  10 | Compact | 10 |   1638 |  17-12-05 19:01:55 | NULL  | NULL  | utf8_general_ci |  NULL | 
+-----------+--------+---------+------------+------+----------------+-------------------------+-------------+------------+-----------------+----------+-
1 row in set (0.00 sec)

查看表的字符集

5.查看表中所有列的字符集

语法：show full columns from 表名;

mysql> show full columns from test_info;

mysql> show full columns from test_info;
+-------+----------+-----------------+------+-----+---------+-------+---------------------------------+---------+
| Field | Type  | Collation  | Null | Key | Default | Extra | Privileges      | Comment |
+-------+----------+-----------------+------+-----+---------+-------+---------------------------------+---------+
| id | int(3) | NULL   | NO | PRI | NULL |  | select,insert,update,references |   |
| name | char(12) | utf8_general_ci | YES |  | NULL |  | select,insert,update,references |   |
| dorm | char(10) | utf8_general_ci | YES |  | NULL |  | select,insert,update,references |   |
| addr | char(12) | utf8_general_ci | YES |  | 未知 |  | select,insert,update,references |   |
| score | int(3) | NULL   | YES |  | NULL |  | select,insert,update,references |   |
+-------+----------+-----------------+------+-----+---------+-------+---------------------------------+---------+
5 rows in set (0.00 sec)

所有列的字符集

二、设置字符集

设置字符集一般有两种方法，一种是在创建表的时候设置字符集，另一种是表建成之后修改字符集。

1.创建时指定字符集

创建库的时候指定字符集：

语法：create database 库名 default character set=字符集；

create database db2 default character set=utf8

创建表的时候指定字符集：

语法：create table 表名（属性）default character set = 字符集；

mysql> create table test1(id int(6),name char(10)) default character set = 'gbk';
Query OK, 0 rows affected (0.39 sec)

2.修改字符集

修改全局字符集

/*建立连接使用的编码*/
set character_set_connection=utf8;
/*数据库的编码*/
set character_set_database=utf8;
/*结果集的编码*/
set character_set_results=utf8;
/*数据库服务器的编码*/
set character_set_server=utf8;

set character_set_system=utf8;

set collation_connection=utf8;

set collation_database=utf8;

set collation_server=utf8;

修改全局字符集

修改库的字符集

语法：alter database 库名 default character set 字符集;

alter database shiyan default character set gbk;

mysql> show create database shiyan\G
*************************** 1. row ***************************
  Database: shiyan
Create Database: CREATE DATABASE `shiyan` /*!40100 DEFAULT CHARACTER SET utf8 */
1 row in set (0.00 sec)

mysql> alter database shiyan default character set gbk;
Query OK, 1 row affected (0.00 sec)

mysql> show create database shiyan\G
*************************** 1. row ***************************
  Database: shiyan
Create Database: CREATE DATABASE `shiyan` /*!40100 DEFAULT CHARACTER SET gbk */
1 row in set (0.00 sec)

修改表的字符集

语法：alter table 表名 convert to character set 字符集;

 alter table test1 convert to character set utf8;

mysql> show create table test1\G
*************************** 1. row ***************************
  Table: test1
Create Table: CREATE TABLE `test1` (
 `id` int(6) DEFAULT NULL,
 `name` char(10) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=gbk #原字符集
1 row in set (0.00 sec)

mysql> alter table test1 convert to character set utf8;
Query OK, 0 rows affected (0.58 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> show create table test1\G
*************************** 1. row ***************************
  Table: test1
Create Table: CREATE TABLE `test1` (
 `id` int(6) DEFAULT NULL,
 `name` char(10) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8 #修改后的字符集
1 row in set (0.00 sec)

修改列表的字符集

修改字段的字符集

语法：alter table 表名 modify 字段名 字段属性 character set gbk；

 alter table test1 modify name char(10) character set gbk;

mysql> show full columns from test1;
+-------+----------+-----------------+------+-----+---------+-------+---------------------------------+---------+
| Field | Type  | Collation  | Null | Key | Default | Extra | Privileges      | Comment |
+-------+----------+-----------------+------+-----+---------+-------+---------------------------------+---------+
| id | int(6) | NULL   | YES |  | NULL |  | select,insert,update,references |   |
| name | char(10) | utf8_general_ci | YES |  | NULL |  | select,insert,update,references |   |
+-------+----------+-----------------+------+-----+---------+-------+---------------------------------+---------+
2 rows in set (0.01 sec)

mysql> alter table test1 modify name char(10) character set gbk;
Query OK, 0 rows affected (0.58 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> show full columns from test1;
+-------+----------+----------------+------+-----+---------+-------+---------------------------------+---------+
| Field | Type  | Collation  | Null | Key | Default | Extra | Privileges      | Comment |
+-------+----------+----------------+------+-----+---------+-------+---------------------------------+---------+
| id | int(6) | NULL   | YES |  | NULL |  | select,insert,update,references |   |
| name | char(10) | gbk_chinese_ci | YES |  | NULL |  | select,insert,update,references |   |
+-------+----------+----------------+------+-----+---------+-------+---------------------------------+---------+
2 rows in set (0.01 sec)

修改字段的字符集