java MySQL 更改为 utf8mb4 后，从服务器收到的字段“224”的错误未知字符集索引
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After MySQL change to utf8mb4, Error Unknown character set index for field '224' received from server
提问by Nick Eng
I've changed our server MySQL database to use utf8mb4 because we need to support emoticon. I have followed the instruction based on How to support full Unicode in MySQL databasesarticle by Mathias Bynens. The only difference is I wasn't changing from utf8.
我已经将我们的服务器 MySQL 数据库更改为使用 utf8mb4，因为我们需要支持表情符号。我已经按照Mathias Bynens 的文章How to support full Unicode in MySQL databases 的说明进行了操作。唯一的区别是我没有从 utf8 改变。
Here's the configuration:
这是配置：
[client]
default-character-set = utf8mb4
[mysql]
default-character-set = utf8mb4
[mysqld]
character-set-client-handshake = FALSE
init-connect = 'SET NAMES utf8mb4'
character-set-server = utf8mb4
collation-server = utf8mb4_unicode_ci
Here is MySQL SHOW VARIABLESoutput:
这是 MySQLSHOW VARIABLES输出：
mysql> SHOW VARIABLES WHERE Variable_name LIKE 'character\_set\_%' OR Variable_name LIKE 'collation%';
+--------------------------+--------------------+
| Variable_name | Value |
+--------------------------+--------------------+
| character_set_client | utf8mb4 |
| character_set_connection | utf8mb4 |
| character_set_database | utf8mb4 |
| character_set_filesystem | binary |
| character_set_results | utf8mb4 |
| character_set_server | utf8mb4 |
| character_set_system | utf8 |
| collation_connection | utf8mb4_unicode_ci |
| collation_database | utf8mb4_unicode_ci |
| collation_server | utf8mb4_unicode_ci |
+--------------------------+--------------------+
10 rows in set (0.00 sec)
After I restarted MySQL & my application, the console printed the error log as below:
在我重新启动 MySQL 和我的应用程序后，控制台打印了如下错误日志：
2014-08-05 17:33:49,022 [com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2] WARN com.mchange.v2.resourcepool.BasicResourcePool - com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@6ae03500 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception:
java.sql.SQLException: Unknown character set index for field '224' received from server.
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:910)
at com.mysql.jdbc.Connection.getCharsetNameForIndex(Connection.java:3556)
at com.mysql.jdbc.Field.<init>(Field.java:192)
at com.mysql.jdbc.MysqlIO.unpackField(MysqlIO.java:731)
at com.mysql.jdbc.MysqlIO.getResultSet(MysqlIO.java:387)
at com.mysql.jdbc.MysqlIO.readResultsForQueryOrUpdate(MysqlIO.java:2076)
at com.mysql.jdbc.MysqlIO.readAllResults(MysqlIO.java:1451)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1787)
at com.mysql.jdbc.Connection.execSQL(Connection.java:3277)
at com.mysql.jdbc.Connection.execSQL(Connection.java:3206)
at com.mysql.jdbc.Statement.executeQuery(Statement.java:1232)
at com.mysql.jdbc.Connection.loadServerVariables(Connection.java:4478)
at com.mysql.jdbc.Connection.initializePropsFromServer(Connection.java:4062)
at com.mysql.jdbc.Connection.createNewIO(Connection.java:2789)
at com.mysql.jdbc.Connection.<init>(Connection.java:1555)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)
at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPoolPooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
at com.mchange.v2.resourcepool.BasicResourcePool.access0(BasicResourcePool.java:32)
at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
Aug 5, 2014 5:33:49 PM org.hibernate.util.JDBCExceptionReporter logExceptions
WARNING: SQL Error: 0, SQLState: null
Aug 5, 2014 5:33:49 PM org.hibernate.util.JDBCExceptionReporter logExceptions
SEVERE: Connections could not be acquired from the underlying database!
Aug 5, 2014 5:33:49 PM org.hibernate.util.JDBCExceptionReporter logExceptions
WARNING: SQL Error: 0, SQLState: null
Aug 5, 2014 5:33:49 PM org.hibernate.util.JDBCExceptionReporter logExceptions
SEVERE: Connections could not be acquired from the underlying database!
Login to my CMS nor API calls don't work. It gave me the above error for which I can't google any solution.
登录到我的 CMS 或 API 调用都不起作用。它给了我上述错误，我无法通过谷歌搜索任何解决方案。
What to do next, in order to fix the error?
为了修复错误，下一步该怎么做？
回答by Jane Tow
I was there too, and I fixed it by simply upgrading the connector to "mysql-connector-java-5.1.30-bin.jar". Hope it would help.
我也在那里，我通过简单地将连接器升级到"mysql-connector-java-5.1.30-bin.jar". 希望它会有所帮助。
Download latest connector from https://dev.mysql.com/downloads/connector/j/
