Mysql 需要支持 emoji 表情符号版本需要大于5.5.3，且字符集需要设置为utf8mb4 字符集。

utf8mb4和utf8到底有什么区别呢？原来以往的mysql的utf8一个字符最多3字节，而utf8mb4则扩展到一个字符最多能有4字节，所以能支持更多的字符集。

将Mysql的编码从utf8转换成utf8mb4。

需要 >= MySQL 5.5.3版本、从库也必须是5.5的了、低版本不支持这个字符集、复制报错

停止MySQL Server服务

修改 my.cnf或者mysql.ini [client]

default-character-set = utf8mb4

[mysql]

default-character-set = utf8mb4

[mysqld]

character-set-client-handshake = FALSE

character-set-server = utf8mb4

collation-server = utf8mb4_unicode_ci

init_connect='SET NAMES utf8mb4'

重启 MySQL Server、检查字符集。

查看服务器字符集设置 mysql> SHOW VARIABLES WHERE Variable_name LIKE 'character%' OR Variable_name LIKE 'collation%'; +--------------------------+--------------------+

| 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 | utf8 |

| collation_connection | utf8mb4_unicode_ci |

| collation_database | utf8mb4_unicode_ci |

| collation_server | utf8mb4_unicode_ci |

+--------------------------+--------------------+

查看数据库字符集 mysql> select * from SCHEMATA where SCHEMA_NAME='ttlsa'; +--------------+-------------+----------------------------+------------------------+----------+

| CATALOG_NAME | SCHEMA_NAME | DEFAULT_CHARACTER_SET_NAME | DEFAULT_COLLATION_NAME | SQL_PATH |

+--------------+-------------+----------------------------+------------------------+----------+

| def | ttlsa | utf8mb4 | utf8mb4_unicode_ci | NULL |

+--------------+-------------+----------------------------+------------------------+----------+

查看表字符集 mysql> select TABLE_SCHEMA,TABLE_NAME,TABLE_COLLATION from information_schema.TABLES; +--------------------+----------------------------------------------------+--------------------+

| TABLE_SCHEMA | TABLE_NAME | TABLE_COLLATION |

+--------------------+----------------------------------------------------+--------------------+

查看列字符集 mysql> select TABLE_SCHEMA,TABLE_NAME,COLUMN_NAME,COLLATION_NAME from COLUMNS; +--------------------+----------------------------------------------------+--------------------------------------------+--------------------+

| TABLE_SCHEMA | TABLE_NAME | COLUMN_NAME | COLLATION_NAME |

+--------------------+----------------------------------------------------+--------------------------------------------+--------------------+

转换字符集语句 use information_schema;

SELECT concat("ALTER DATABASE `",table_schema,"` CHARACTER SET = utf8mb4 COLLATE = utf8mb4_unicode_ci;") as _sql

FROM `TABLES` where table_schema like "DB_NAME" group by table_schema;

SELECT concat("ALTER TABLE `",table_schema,"`.`",table_name,"` CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;") as _sql

FROM `TABLES` where table_schema like "DB_NAME" group by table_schema, table_name;

SELECT concat("ALTER TABLE `",table_schema,"`.`",table_name, "` CHANGE `",column_name,"` `",column_name,"` ",data_type,"(",character_maximum_length,") CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;") as _sql

FROM `COLUMNS` where table_schema like "DB_NAME" and data_type in ('varchar');

SELECT concat("ALTER TABLE `",table_schema,"`.`",table_name, "` CHANGE `",column_name,"` `",column_name,"` ",data_type," CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;") as _sql

FROM `COLUMNS` where table_schema like "DB_NAME" and data_type in ('text','tinytext','mediumtext','long