多少版本的mysql支持表情符号

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

?1234567891011 [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

?1 mysql>SHOW VARIABLES WHERE Variable_name LIKE 'character%' OR Variable_name LIKE 'collation%'

?1234567891011121314 +--------------------------+--------------------+ | 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

?1 mysql>select * from SCHEMATA where SCHEMA_NAME='ttlsa'

?12345 +--------------+-------------+----------------------------+------------------------+----------+ | 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

?1 mysql>select TABLE_SCHEMA,TABLE_NAME,TABLE_COLLATION from information_schema.TABLES

?123 +--------------------+----------------------------------------------------+--------------------+ | TABLE_SCHEMA| TABLE_NAME | TABLE_COLLATION | +--------------------+----------------------------------------------------+--------------------+

查看列字符集

?1 mysql>select TABLE_SCHEMA,TABLE_NAME,COLUMN_NAME,COLLATION_NAME from COLUMNS

?123 +--------------------+----------------------------------------------------+--------------------------------------------+--------------------+ | TABLE_SCHEMA| TABLE_NAME | COLUMN_NAME| COLLATION_NAME | +--------------------+----------------------------------------------------+--------------------------------------------+--------------------+

转换字符集语句

?123456789 use information_schemaSELECT 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_schemaSELECT 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_nameSELECT 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'

从

mysql

5.5.3

开始，mysql

支持一种

utf8mb4

的字符集，这个字符集能够支持

4

字节的

utf8

编码的字符。

utf8mb4

字符集能够完美地向下兼容

utf8

字符串。在数据存储方面，当一个普通中文字符存入数据库时仍然占用

3

个字节，在存入一个

unified

emoji

表情的时候，它会自动占用

4

个字节。所以在输入输出时都不会存在乱码的问题了。由于

utf8mb4

是

utf8

的超集，从

utf8

升级到

utf8mb4

不会有任何问题，直接升级即可；如果从别的字符集如

gb2312

或者

gbk

转化而来，一定要先备份数据库。然后，修改

mysql

的配置文件

/etc/my.cnf，修改连接默认字符集为

utf8mb4

，然后在连接数据库以后首先执行一句

sql:

set

names

utf8mb4。

1.

修改my.cnf

或

my.ini

[mysqld]

character-set-server=utf8mb4

[mysql]

default-character-set=utf8mb4

修改后重启mysql

登陆mysql，

show

variables

like

'character%'

可以查看编码是否已经修改成功。

2、修改数据库和数据表为相应的

utf8mb4

格式。

alter

table

table_name

convert

to

character

set

utf8mb4

collate

utf8mb4_bin

3、在代码中，连接数据库成功后，执行

"set

names

utf8mb4"

---