Question

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，请在 GitHub 上提交 issue。

另请参阅

• SHOW [GLOBAL|SESSION] VARIABLES
• SET <variable>
• Character Set Support