使MySQL能够存储emoji表情字符的设置教程

[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'

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 |
+--------------------------+--------------------+

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   |
+--------------+-------------+----------------------------+------------------------+----------+

mysql> select TABLE_SCHEMA,TABLE_NAME,TABLE_COLLATION from information_schema.TABLES;

+--------------------+----------------------------------------------------+--------------------+
| TABLE_SCHEMA    | TABLE_NAME                     | TABLE_COLLATION  |
+--------------------+----------------------------------------------------+--------------------+

mysql> select TABLE_SCHEMA,TABLE_NAME,COLUMN_NAME,COLLATION_NAME from COLUMNS;

+--------------------+----------------------------------------------------+--------------------------------------------+--------------------+
| TABLE_SCHEMA    | TABLE_NAME                     | COLUMN_NAME                | COLLATION_NAME   |
+--------------------+----------------------------------------------------+--------------------------------------------+--------------------+

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