SET [NAMES|CHARACTER SET]
SET NAMES，SET CHARACTER SET 和 SET CHARSET 语句用于修改当前连接的变量 character_set_client，character_set_results 和 character_set_connection。
语法图
SetNamesStmt:
VariableAssignmentList:
VariableAssignment:
CharsetName:
StringName:
CharsetKw:
CharsetNameOrDefault:
示例
SHOW VARIABLES LIKE 'character_set%';
+--------------------------+--------------------------------------------------------+
| Variable_name | Value |
+--------------------------+--------------------------------------------------------+
| character_sets_dir | /usr/local/mysql-5.6.25-osx10.8-x86_64/share/charsets/ |
| character_set_connection | utf8mb4 |
| character_set_system | utf8 |
| character_set_results | utf8mb4 |
| character_set_client | utf8mb4 |
| character_set_database | utf8mb4 |
| character_set_filesystem | binary |
| character_set_server | utf8mb4 |
+--------------------------+--------------------------------------------------------+
8 rows in set (0.01 sec)
SET NAMES utf8;
Query OK, 0 rows affected (0.00 sec)
SHOW VARIABLES LIKE 'character_set%';
+--------------------------+--------------------------------------------------------+
| Variable_name | Value |
+--------------------------+--------------------------------------------------------+
| character_sets_dir | /usr/local/mysql-5.6.25-osx10.8-x86_64/share/charsets/ |
| character_set_connection | utf8 |
| character_set_system | utf8 |
| character_set_results | utf8 |
| character_set_client | utf8 |
| character_set_server | utf8mb4 |
| character_set_database | utf8mb4 |
| character_set_filesystem | binary |
+--------------------------+--------------------------------------------------------+
8 rows in set (0.00 sec)
SET CHARACTER SET utf8mb4;
Query OK, 0 rows affected (0.00 sec)
SHOW VARIABLES LIKE 'character_set%';
+--------------------------+--------------------------------------------------------+
| Variable_name | Value |
+--------------------------+--------------------------------------------------------+
| character_set_connection | utf8mb4 |
| character_set_system | utf8 |
| character_set_results | utf8mb4 |
| character_set_client | utf8mb4 |
| character_sets_dir | /usr/local/mysql-5.6.25-osx10.8-x86_64/share/charsets/ |
| character_set_database | utf8mb4 |
| character_set_filesystem | binary |
| character_set_server | utf8mb4 |
+--------------------------+--------------------------------------------------------+
8 rows in set (0.00 sec)
MySQL 兼容性
SET [NAMES|CHARACTER SET] 语句与 MySQL 完全兼容。如发现任何兼容性差异，请尝试 TiDB 支持资源。