MySQL5中大数据错误：Packet for query is too large (****** > ******). You can change this value on the server by setting the max_allowed_packet' variable.;

使用的MySQL数据库版本：5.5

插入或更新字段有大数据时（大于1M），会出现如下错误：

### Cause: com.mysql.jdbc.PacketTooBigException: Packet for query is too large (1132484 > 1048576). You can change this value on the server by setting the max_allowed_packet' variable.
; SQL []; Packet for query is too large (1132484 > 1048576). You can change this value on the server by setting the max_allowed_packet' variable.; nested exception is com.mysql.jdbc.PacketTooBigException: Packet for query is too large (1132484 > 1048576). You can change this value on the server by setting the max_allowed_packet' variable.] with root cause
com.mysql.jdbc.PacketTooBigException: Packet for query is too large (1132484 > 1048576). You can change this value on the server by setting the max_allowed_packet' variable.
    at com.mysql.jdbc.MysqlIO.send(MysqlIO.java:3910)
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2596)
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2776)
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2838)
    at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2082)
    at com.mysql.jdbc.PreparedStatement.execute(PreparedStatement.java:1307)
    at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.execute(NewProxyPreparedStatement.java:989)
    at org.apache.ibatis.executor.statement.PreparedStatementHandler.update(PreparedStatementHandler.java:44)
    at org.apache.ibatis.executor.statement.RoutingStatementHandler.update(RoutingStatementHandler.java:69)
    at org.apache.ibatis.executor.SimpleExecutor.doUpdate(SimpleExecutor.java:48)
    at org.apache.ibatis.executor.BaseExecutor.update(BaseExecutor.java:105)
    at org.apache.ibatis.executor.CachingExecutor.update(CachingExecutor.java:71)
    at org.apache.ibatis.session.defaults.DefaultSqlSession.update(DefaultSqlSession.java:152)
    at org.apache.ibatis.session.defaults.DefaultSqlSession.insert(DefaultSqlSession.java:141)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:358)
    at com.sun.proxy.$Proxy97.insert(Unknown Source)
    at org.mybatis.spring.SqlSessionTemplate.insert(SqlSessionTemplate.java:240)
    at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:51)
    at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:52)
    at com.sun.proxy.$Proxy98.insertClient(Unknown Source)
    at com.shiliu.game.service.impl.ExcelUserServiceImpl.insertClient(ExcelUserServiceImpl.java:35)
    at com.shiliu.game.controller.ClientController.batchimport(ClientController.java:171)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:219)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:745)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:686)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:936)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:838)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:812)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1008)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

报错原因：

开始以为是相应字段的类型设置不正确，超出了字段的最大范围，网上查询后发现是mysql默认加载的数据文件不超过1M，可以通过更改mysql的配置文件my.cnf（Linux，或windows的my.ini）来更改这一默认值，从而达到插入大数据的目的。

解决方法：

　　1.SQL查询下设置最大值

　　　　SHOW VARIABLES LIKE '%max_allowed_packet%';

　　2.找到MySQL安装目录修改my.ini配置文件

　　3.查找是否存在 max_allowed_packet 字段，若有则修改其参数，没有则添加。

　　4.添加 max_allowed_packet 字段

　　　　[mysqld]

　　　　max_allowed_packet = 20M

5.重启数据库：

6.再查询是否设置成功。

有时候命令“SET GLOBAL max_allowed_packet=16*1024*1024”无效

需要使用如下命令：set @@max_allowed_packet=5*1024*1024（这个我试了也无效..）

附加：三若

　　若数据库配置不能做修改

　　若入你使用的是MyBatis，做添加或修改

　　若你想知道java 中 list集合中有几十万条数据,每100条为一组取出来如何实现

　　　　请点击我！