我用java从Mysql查询了一些记录。但在一个持续时间的某些查询中,我遇到了一个使查询失败的问题,但在另一些查询中,查询成功。该错误信息是未来:CommunicationsException:通信链路故障
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 90 milliseconds ago. The last packet sent successfully to the server was 1,674 milliseconds ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1116)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3090)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2979)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3520)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:935)
at com.mysql.jdbc.MysqlIO.nextRow(MysqlIO.java:1433)
at com.mysql.jdbc.MysqlIO.readSingleRowSet(MysqlIO.java:2924)
at com.mysql.jdbc.MysqlIO.getResultSet(MysqlIO.java:477)
at com.mysql.jdbc.MysqlIO.readResultsForQueryOrUpdate(MysqlIO.java:2619)
at com.mysql.jdbc.MysqlIO.readAllResults(MysqlIO.java:1788)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2209)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2619)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2569)
at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1521)
......
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader.main(JarRsrcLoader.java:58)
Caused by: java.io.IOException: Packets received out of order
at com.mysql.jdbc.MysqlIO.readRemainingMultiPackets(MysqlIO.java:3152)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3077)
... 23 more
我已经尝试了一些方法,比如像:
- 设置
max_allowed_packet = 128 * 1024 * 1024
在/etc/my.conf
- 添加
?autoReconnect=true&failOverReadOnly=false&maxReconnects=10
我的连接网址
但没有任何反应。
我的环境是:
- MySQL的:5.5.3-M3的日志源分布
- 的Java:1.6.0_16
- 的jdk:热点(TM)64位服务器VM(建14.2 -b01,混合模式)
- JDBC:MySQL的连接器,Java的5.1.18
在操作中,我使用了'group_concat',并且我的连接字符串非常长。我也尝试使用PHP的查询,它运作良好。当我设置'group_concat_max_len' <32M时,它会通过GROUP_CONCAT()剪切一些数据并返回成功。但是,如果group_concat_max_len> 32M,则失败。 – zhouzuan2k
可能的[MySQL-JDBC:Communications Link Failure]重复(http://stackoverflow.com/questions/2121829/mysql-jdbc-communications-link-failure) – CloudyMarble