sql-statement-set-names.md

title	summary	aliases
SET [NAMES|CHARACTER SET]	TiDB 数据库中 SET [NAMES|CHARACTER SET] 的使用概况。	/docs-cn/dev/sql-statements/sql-statement-set-names/ /docs-cn/dev/reference/sql/statements/set-names/

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 ::=
    "SET" ("NAMES" ("DEFAULT" | CharsetName ("COLLATE" ("DEFAULT" | CollationName))?) | ("CHARSET" | ("CHAR" | "CHARACTER") "SET") ("DEFAULT" | CharsetName))

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。

另请参阅

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