mysql - MySQL 配置使用 utf8 字符编码的 JDBC url

Question

MySQL 5.6 配置

我已手动配置 /etc/mysql/my.cnf 以使用 utf8。见下文:

[mysqld]
character-set-server=utf8
character-sets-dir=/usr/share/mysql/charsets

[mysql]
character-sets-dir=/usr/share/mysql/charsets default-character-set=utf8

[mysqladmin]
character-sets-dir=/usr/share/mysql/charsets default-character-set=utf8

[mysqlcheck]
character-sets-dir=/usr/share/mysql/charsets default-character-set=utf8

[mysqldump]
character-sets-dir=/usr/share/mysql/charsets default-character-set=utf8

[mysqlimport]
character-sets-dir=/usr/share/mysql/charsets default-character-set=utf8

[mysqlshow]
character-sets-dir=/usr/share/mysql/charsets default-character-set=utf8

[client]
character-sets-dir=/usr/share/mysql/charsets default-character-set=utf8

从控制台:

mysql> show variables like 'char%';
+--------------------------+----------------------------+
| Variable_name            | Value                      |
+--------------------------+----------------------------+
| character_set_client     | utf8                       |
| character_set_connection | utf8                       |
| character_set_database   | utf8                       |
| character_set_filesystem | binary                     |
| character_set_results    | utf8                       |
| character_set_server     | utf8                       |
| character_set_system     | utf8                       |
| character_sets_dir       | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+
8 rows in set (0.01 sec)

应用配置

现在对于网络应用程序，我在 Tomcat 的 context.xml

中使用了这两个连接 url

url="jdbc:mysql://localhost:3306/test?autoReconnect=true&useUnicode=true&characterEncoding=UTF-8"

url="jdbc:mysql://localhost:3306/test?autoReconnect=true&useUnicode=true&characterEncoding=UTF-8&characterSetResults=utf8&connectionCollation=utf8_general_ci"

以上不起作用，并为我提供以下应用程序。

show variables like 'char%';
+--------------------------+----------------------------+
| Variable_name            | Value                      |
+--------------------------+----------------------------+
| character_set_client     | utf8mb4                    |
| character_set_connection | utf8                       |
| character_set_database   | utf8                       |
| character_set_filesystem | binary                     |
| character_set_results    | utf8mb4                    |
| character_set_server     | utf8                       |
| character_set_system     | utf8                       |
| character_sets_dir       | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+

---

这里可能有什么问题？为什么显示 utf8mb4 而不是 utf8？

Answer 1

您可能需要处理以下内容:

Changes in MySQL Connector/J 5.1.13 (2010-06-24)

• Connector/J 不支持服务器 5.5.2 及更新版本的 utf8mb4。

  Connector/J 现在自动检测配置有 character_set_server=utf8mb4 的服务器，或将使用 characterEncoding=... 传递的 Java 编码 utf-8 视为 utf8mb4 在 SET NAMES= 调用中建立连接。 (漏洞 #54175)