mysql - MySQL 5.5 Connector / J CharacterSet编码（utf8mb4）问题

我正在尝试将utf8mb4字符串正确存储到MySQL 5.5.30中。我们正在使用ConnectorJ 5.1.18。

根据文档，ConnectorJ应根据character_set_server变量自动检测字符编码......

但是，尽管我可以告诉它总是默认为

SET NAMES latin1而不是SET NAMES utf8mb4

连接器-j探查器的日志输出：

Sat Jul 06 15:45:20 CDT 2013 INFO: Profiler Event: [QUERY]  at java.sql.DriverManager.getConnection(DriverManager.java:579) duration: 1 ms, connection-id: 57, statement-id: 3, resultset-id: 4, message: /* mysql-connector-java-5.1.18 ( Revision: tonci.grgin@oracle.com-20110930151701-jfj14ddfq48ifkfq ) */SHOW VARIABLES WHERE Variable_name ='language' OR Variable_name = 'net_write_timeout' OR Variable_name = 'interactive_timeout' OR Variable_name = 'wait_timeout' OR Variable_name = 'character_set_client' OR Variable_name = 'character_set_connection' OR Variable_name = 'character_set' OR Variable_name = 'character_set_server' OR Variable_name = 'tx_isolation' OR Variable_name = 'transaction_isolation' OR Variable_name = 'character_set_results' OR Variable_name = 'timezone' OR Variable_name = 'time_zone' OR Variable_name = 'system_time_zone' OR Variable_name = 'lower_case_table_names' OR Variable_name = 'max_allowed_packet' OR Variable_name = 'net_buffer_length' OR Variable_name = 'sql_mode' OR Variable_name = 'query_cache_type' OR Variable_name = 'query_cache_size' OR Variable_name = 'init_connect'
Sat Jul 06 15:45:20 CDT 2013 INFO: Profiler Event: [FETCH]  at java.sql.DriverManager.getConnection(DriverManager.java:579) duration: 0 ms, connection-id: 57, statement-id: 3, resultset-id: 4
Sat Jul 06 15:45:20 CDT 2013 INFO: Profiler Event: [QUERY]  at java.sql.DriverManager.getConnection(DriverManager.java:579) duration: 0 ms, connection-id: 57, statement-id: 3, resultset-id: 5, message: /* mysql-connector-java-5.1.18 ( Revision: tonci.grgin@oracle.com-20110930151701-jfj14ddfq48ifkfq ) */SELECT @@session.auto_increment_increment
Sat Jul 06 15:45:20 CDT 2013 INFO: Profiler Event: [FETCH]  at java.sql.DriverManager.getConnection(DriverManager.java:579) duration: 0 ms, connection-id: 57, statement-id: 3, resultset-id: 5
Sat Jul 06 15:45:20 CDT 2013 INFO: Profiler Event: [QUERY]  at java.sql.DriverManager.getConnection(DriverManager.java:579) duration: 0 ms, connection-id: 57, statement-id: 4, resultset-id: 6, message: SHOW COLLATION
Sat Jul 06 15:45:20 CDT 2013 INFO: Profiler Event: [FETCH]  at java.sql.DriverManager.getConnection(DriverManager.java:579) duration: 3 ms, connection-id: 57, statement-id: 4, resultset-id: 6
Sat Jul 06 15:45:20 CDT 2013 INFO: Profiler Event: [QUERY]  at java.sql.DriverManager.getConnection(DriverManager.java:579) duration: 1 ms, connection-id: 57, statement-id: 999, resultset-id: 0, message: SET NAMES latin1

SHOW VARIABLES调用的输出如下：

character_set_client        utf8
character_set_connection    utf8
character_set_results       utf8
character_set_server        utf8mb4

服务器当前正在运行，因此要更新character_set_server值，我只需运行

SET GLOBAL

和

SET

语句。

更新：当我更改my.cnf中的character_set_server值并重新启动我的服务器时，ConnectorJ完全按照预期检测到utf8mb4。

当我使用SET GLOBAL手动设置值时，ConnectorJ继续使用Latin1。

有人知道为什么会这样吗？有没有办法以ConnectorJ检测的方式更新字符集而不必使mysql脱机？

我有类似的问题。过去，ConnectorJ的客户端字符集握手过去常常使用常规/不完整utf8字符集而不是utf8mb4

https://dev.mysql.com/doc/relnotes/connector-j/en/news-5-1-13.html

修复自5.1.12版以来发现的错误。 Connector / J现在自动检测使用character_set_server = utf8mb4配置的服务器，或者在SET NAMES =在建立连接时进行的调用中使用characterEncoding = ...作为utf8mb4处理传递的Java编码utf-8。（Bug＃54175）

但是，升级ConnectorJ并没有解决任何问题。顺便说一句，要知道更改配置文件修复了问题，而在运行时更改值则没有。这为我节省了很多时间。

对于任何因任何原因无法重启服务器的问题。我建议（当你想使用utf8mb4时，与连接字符串中省略characterEncoding的MySQL文档相反）将characterEncoding=UTF-8添加到连接字符串并在其上执行手册SET NAMES utf8mb4连接你遇到了麻烦。

MySQL 5.5 Connector / J CharacterSet编码（utf8mb4）问题

1 个答案: