MySQL查看字符集以及修改字符集

一、查看数据库字符集

1、进入数据库

[root@localhost ~]# mysql
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Your MySQL connection id is 138
Server version: 5.7.34 MySQL Community Server (GPL)

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mysql>  

2、查看MySQL字符集

根据系统的不同（数据库版本也有可能），安装数据库时字符集也可能不同11

mysql>  show variables like 'character%';
+--------------------------+--------------------------------------------------------------+
| Variable_name            | Value                                                        |
+--------------------------+--------------------------------------------------------------+
| character_set_client     | utf8                                                         |
| character_set_connection | utf8                                                         |
| character_set_database   | latin1                                                       |
| character_set_filesystem | binary                                                       |
| character_set_results    | utf8                                                         |
| character_set_server     | latin1                                                       |
| character_set_system     | utf8                                                         |
| character_sets_dir       | /usr/src/mysql-5.7.34-linux-glibc2.12-x86_64/share/charsets/ |
+--------------------------+--------------------------------------------------------------+
8 rows in set (0.01 sec)


mysql>  show variables like 'collation%';
+----------------------+-------------------+
| Variable_name        | Value             |
+----------------------+-------------------+
| collation_connection | utf8_general_ci   |
| collation_database   | latin1_swedish_ci |
| collation_server     | latin1_swedish_ci |
+----------------------+-------------------+
3 rows in set (0.00 sec)

3、字符集解释

系统变量：
– character_set_client：客户端来源数据使用的字符集

– character_set_connection：连接层字符集

– character_set_database：当前选中数据库的默认字符集

– character_set_results：查询结果字符集

– character_set_filesystem：用于没有字符集导入符的文字和数字－字符串转换

– character_set_server：默认的内部操作字符集

– character_set_system：系统元数据(字段名等)字符集

– 还有以collation_开头的同上面对应的变量，用来描述字符序。

查看MYSQL所支持的字符集

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 |
| utf16le  | UTF-16LE Unicode                | utf16le_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 |
| gb18030  | China National Standard GB18030 | gb18030_chinese_ci  |      4 |
+----------+---------------------------------+---------------------+--------+
41 rows in set (0.00 sec)

这两条命令都是一样的

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 |
| utf16le  | UTF-16LE Unicode                | utf16le_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 |
| gb18030  | China National Standard GB18030 | gb18030_chinese_ci  |      4 |
+----------+---------------------------------+---------------------+--------+
41 rows in set (0.01 sec)

4、查看库的字符集

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| ly                 |
| mysql              |
| performance_schema |
| sys                |
| zabbix             |
+--------------------+
6 rows in set (0.00 sec)

mysql> show create database ly\G
*************************** 1. row ***************************
       Database: ly
Create Database: CREATE DATABASE `ly` /*!40100 DEFAULT CHARACTER SET latin1 */  #字符集 latin1 
1 row in set (0.00 sec)



mysql> show create database mysql\G
*************************** 1. row ***************************
       Database: mysql
Create Database: CREATE DATABASE `mysql` /*!40100 DEFAULT CHARACTER SET latin1 */  #字符集 latin1
1 row in set (0.00 sec)



mysql> show create database zabbix\G
*************************** 1. row ***************************
       Database: zabbix
Create Database: CREATE DATABASE `zabbix` /*!40100 DEFAULT CHARACTER SET utf8 COLLATE utf8_bin */ #字符集utf8
1 row in set (0.00 sec)

5、查看表的字符集

mysql> show tables;
+--------------+
| Tables_in_ly |
+--------------+
| gw           |
+--------------+
1 row in set (0.00 sec)


mysql> show create  table  gw\G
*************************** 1. row ***************************
       Table: gw
Create Table: CREATE TABLE `gw` (
  `id` int(100) DEFAULT NULL,
  `name` varchar(100) CHARACTER SET latin1 DEFAULT NULL,
  `sex` varchar(100) CHARACTER SET latin1 DEFAULT NULL,
  `age` int(100) DEFAULT NULL,
  `stature` int(100) DEFAULT NULL,
  `weight` int(100) DEFAULT NULL,
  `telephone` int(100) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8
1 row in set (0.00 sec)  #字符集 CHARSET=utf8

二、修改MySQL字符集

1、修改库的字符集

查看字符集

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| ly                 |
| mysql              |
| performance_schema |
| sys                |
| zabbix             |
+--------------------+
6 rows in set (0.00 sec)


mysql> show create database ly\G
*************************** 1. row ***************************
       Database: ly
Create Database: CREATE DATABASE `ly` /*!40100 DEFAULT CHARACTER SET latin1 */
1 row in set (0.01 sec)

修改字符集

# 语法：alter database  database_name default  charset  字符集名称;

mysql> alter database ly default charset utf8;
Query OK, 1 row affected (0.00 sec)

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

注意：修改库字符集后库里面的表不会随着库的字符集更改而更改（如果在库里创建表时不指定字符集，这个表的字符集会默认是库的字符集）

2、修改表级字符集

查看表的字符集（进入到需要修改表的库中）

mysql> show create table gw\G
*************************** 1. row ***************************
       Table: gw
Create Table: CREATE TABLE `gw` (
  `id` int(100) DEFAULT NULL,
  `name` varchar(100) DEFAULT NULL,
  `sex` varchar(100) DEFAULT NULL,
  `age` int(100) DEFAULT NULL,
  `stature` int(100) DEFAULT NULL,
  `weight` int(100) DEFAULT NULL,
  `telephone` int(100) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1    #字符集 CHARSET=latin1 
1 row in set (0.00 sec)

修改表的字符集

# 语法：alter table  table_name default  charset  字符集名称;

mysql> alter table gw default charset utf8;
Query OK, 0 rows affected (0.01 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> show create table gw\G
*************************** 1. row ***************************
       Table: gw
Create Table: CREATE TABLE `gw` (
  `id` int(100) DEFAULT NULL,
  `name` varchar(100) CHARACTER SET latin1 DEFAULT NULL,
  `sex` varchar(100) CHARACTER SET latin1 DEFAULT NULL,
  `age` int(100) DEFAULT NULL,
  `stature` int(100) DEFAULT NULL,
  `weight` int(100) DEFAULT NULL,
  `telephone` int(100) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8  #表的字符集已修改
1 row in set (0.00 sec)

3、创建库或创建表时指定字符集

创建库指定字符集

#语法  create database database_name default charset 字符集;

mysql> create database 中关村 default charset utf8;
Query OK, 1 row affected (0.00 sec)

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| 中关村              |
| ly                 |
| mysql              |
| performance_schema |
| sys                |
| ww                 |
| zabbix             |
+--------------------+
9 rows in set (0.00 sec)

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

创建表时指定字符集

mysql>create table 档案( 编号 int(100) DEFAULT NULL, 姓名 varchar(100) DEFAULT NULL,年龄 int(100) DEFAULT NULL) DEFAULT CHARSET utf8;
Query OK, 1 row affected (0.00 sec)


mysql> show create table 档案\G
*************************** 1. row ***************************
       Table: 档案
Create Table: CREATE TABLE `档案` (
  `编号` int(100) DEFAULT NULL,
  `姓名` varchar(100) DEFAULT NULL,
  `年龄` int(100) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8
1 row in set (0.00 sec)

mysql> desc 档案;
+--------+--------------+------+-----+---------+-------+
| Field  | Type         | Null | Key | Default | Extra |
+--------+--------------+------+-----+---------+-------+
| 编号   | int(100)     | YES  |     | NULL    |       |
| 姓名   | varchar(100) | YES  |     | NULL    |       |
| 年龄   | int(100)     | YES  |     | NULL    |       |
+--------+--------------+------+-----+---------+-------+
3 rows in set (0.00 sec)