早期MySQL版本默认为latin1，从MySQL8.0开始默认字符集已经为 utf8mb4 我这里使用的是mysql8.0 查看支持所有字符集：
mysql> SHOW CHARACTER SET; 返回结果 +----------+---------------------------------+---------------------+--------+ | Charset | Description | Default collation | Maxlen | +----------+---------------------------------+---------------------+--------+ | armscii8 | ARMSCII-8 Armenian | armscii8_general_ci | 1 | | ascii | US ASCII | ascii_general_ci | 1 | | big5 | Big5 Traditional Chinese | big5_chinese_ci | 2 | | binary | Binary pseudo charset | binary | 1 | | cp1250 | Windows Central European | cp1250_general_ci | 1 | | cp1251 | Windows Cyrillic | cp1251_general_ci | 1 | | cp1256 | Windows Arabic | cp1256_general_ci | 1 | | cp1257 | Windows Baltic | cp1257_general_ci | 1 | | cp850 | DOS West European | cp850_general_ci | 1 | | cp852 | DOS Central European | cp852_general_ci | 1 | | cp866 | DOS Russian | cp866_general_ci | 1 | | cp932 | SJIS for Windows Japanese | cp932_japanese_ci | 2 | | dec8 | DEC West European | dec8_swedish_ci | 1 | | eucjpms | UJIS for Windows Japanese | eucjpms_japanese_ci | 3 | | euckr | EUC-KR Korean | euckr_korean_ci | 2 | | gb18030 | China National Standard GB18030 | gb18030_chinese_ci | 4 | | gb2312 | GB2312 Simplified Chinese | gb2312_chinese_ci | 2 | | gbk | GBK Simplified Chinese | gbk_chinese_ci | 2 | | geostd8 | GEOSTD8 Georgian | geostd8_general_ci | 1 | | greek | ISO 8859-7 Greek | greek_general_ci | 1 | | hebrew | ISO 8859-8 Hebrew | hebrew_general_ci | 1 | | hp8 | HP West European | hp8_english_ci | 1 | | keybcs2 | DOS Kamenicky Czech-Slovak | keybcs2_general_ci | 1 | | koi8r | KOI8-R Relcom Russian | koi8r_general_ci | 1 | | koi8u | KOI8-U Ukrainian | koi8u_general_ci | 1 | | 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 | | macce | Mac Central European | macce_general_ci | 1 | | macroman | Mac West European | macroman_general_ci | 1 | | sjis | Shift-JIS Japanese | sjis_japanese_ci | 2 | | swe7 | 7bit Swedish | swe7_swedish_ci | 1 | | tis620 | TIS620 Thai | tis620_thai_ci | 1 | | ucs2 | UCS-2 Unicode | ucs2_general_ci | 2 | | ujis | EUC-JP Japanese | ujis_japanese_ci | 3 | | utf16 | UTF-16 Unicode | utf16_general_ci | 4 | | utf16le | UTF-16LE Unicode | utf16le_general_ci | 4 | | utf32 | UTF-32 Unicode | utf32_general_ci | 4 | | utf8 | UTF-8 Unicode | utf8_general_ci | 3 | | utf8mb4 | UTF-8 Unicode | utf8mb4_0900_ai_ci | 4 | +----------+---------------------------------+---------------------+--------+ 41 rows in set (0.01 sec)
查看当前字符集的使用情况
mysql> show variables like 'character%'; +--------------------------+----------------------------------------------------------------+ | Variable_name | Value | +--------------------------+----------------------------------------------------------------+ | character_set_client | utf8mb4 | | character_set_connection | utf8mb4 | | character_set_database | utf8mb4 | | character_set_filesystem | binary | | character_set_results | utf8mb4 | | character_set_server | utf8mb4 | | character_set_system | utf8mb3 | | character_sets_dir | /usr/local/mysql-8.0.28-linux-glibc2.12-x86_64/share/charsets/ | +--------------------------+----------------------------------------------------------------+ 8 rows in set (0.00 sec)
查看支持所有的排序规则：
mysql> show collation;
查看当前使用的排序规则
mysql> show variables like 'collation%'; +----------------------+--------------------+ | Variable_name | Value | +----------------------+--------------------+ | collation_connection | utf8mb4_0900_ai_ci | | collation_database | utf8mb4_0900_ai_ci | | collation_server | utf8mb4_0900_ai_ci | +----------------------+--------------------+ 3 rows in set (0.00 sec)
设置服务器默认的字符集
[root@centos7 ~]# vim /etc/my.cnf 在[mysqld]语句中任意一行，写入一下内容 character-set-server=utf8mb4 例子： [mysqld] user=mysql basedir=/usr/local/mysql datadir=/data/mysql/data_3306 socket=/tmp/mysql.sock server_id=1 log_bin=/data/mysql/binlog_3306 port=3306 secure_file_priv = /data character-set-server=utf8mb4 ##这是加入的内容 [mysql] socket=/tmp/mysql.sock 修改好以后需要重启mysql才能生效，生产环境不建议改动，新环境可以改动 [root@centos7 ~]# systemctl restart mysqld
设置mysql客户端默认的字符集
[root@centos7 ~]# vim /etc/my.cnf 在[mysql]字段任意一行添加如下内容 default-character-set=utf8mb4 例子： [mysqld] user=mysql basedir=/usr/local/mysql datadir=/data/mysql/data_3306 socket=/tmp/mysql.sock server_id=1 log_bin=/data/mysql/binlog_3306 port=3306 secure_file_priv = /data character-set-server=utf8mb4 [mysql] socket=/tmp/mysql.sock default-character-set=utf8mb4 ##这是加入的内容
MariaDB [(none)]> select version(); +-----------------+ | version() | +-----------------+ | 10.3.35-MariaDB | +-----------------+ 1 row in set (0.000 sec)
查看mariadb10.3.35的默认字符集
MariaDB [(none)]> 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/share/mariadb/charsets/ | +--------------------------+------------------------------+ 8 rows in set (0.001 sec)
MariaDB [(none)]> 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 (0.001 sec)
范例：MySQL 8.0 默认的字符集和排序规则
mysql> select version(); +-----------+ | version() | +-----------+ | 8.0.28 | +-----------+ 1 row in set (0.00 sec)
mysql> show variables like 'character%'; +--------------------------+----------------------------------------------------------------+ | Variable_name | Value | +--------------------------+----------------------------------------------------------------+ | character_set_client | utf8mb4 | | character_set_connection | utf8mb4 | | character_set_database | utf8mb4 | | character_set_filesystem | binary | | character_set_results | utf8mb4 | | character_set_server | utf8mb4 | | character_set_system | utf8mb3 | | character_sets_dir | /usr/local/mysql-8.0.28-linux-glibc2.12-x86_64/share/charsets/ | +--------------------------+----------------------------------------------------------------+ 8 rows in set (0.00 sec)
mysql> show variables like 'collation%'; +----------------------+--------------------+ | Variable_name | Value | +----------------------+--------------------+ | collation_connection | utf8mb4_0900_ai_ci | | collation_database | utf8mb4_0900_ai_ci | | collation_server | utf8mb4_0900_ai_ci | +----------------------+--------------------+ 3 rows in set (0.00 sec)