使MySQL能夠存儲(chǔ)emoji表情字符的設(shè)置教程

更新時(shí)間：2015年12月23日 16:06:36 投稿：goldensun

這篇文章主要介紹了使MySQL能夠存儲(chǔ)emoji表情字符的設(shè)置教程,關(guān)鍵在于utf8mb4字符集的設(shè)置,需要的朋友可以參考下

MySQL 需要支持 emoji 表情符號(hào)版本需要大于5.5.3，且字符集需要設(shè)置為utf8mb4 字符集。

utf8mb4和utf8到底有什么區(qū)別呢？原來(lái)以往的mysql的utf8一個(gè)字符最多3字節(jié)，而utf8mb4則擴(kuò)展到一個(gè)字符最多能有4字節(jié)，所以能支持更多的字符集。

將Mysql的編碼從utf8轉(zhuǎn)換成utf8mb4。

需要 >= MySQL 5.5.3版本、從庫(kù)也必須是5.5的了、低版本不支持這個(gè)字符集、復(fù)制報(bào)錯(cuò)

停止MySQL Server服務(wù)

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'

重啟 MySQL Server、檢查字符集。

查看服務(wù)器字符集設(shè)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 |
+--------------------------+--------------------+

查看數(shù)據(jù)庫(kù)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   |
+--------------------+----------------------------------------------------+--------------------------------------------+--------------------+

轉(zhuǎn)換字符集語(yǔ)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

您可能感興趣的文章: