服务器：windows server 2008R2
mysql： 5.5.19
druid：druid-1.0.26.jar
环境： nginx+redis+tomcat1+tomcat2
tomcat：7.0.29
连接参数：useUnicode=true&characterEncoding=utf-8&autoReconnect=true&failOverReadOnly=false

功能为：将用户新增到用户表
流程：先将该账号去用户表查询，没有则增加

错误问题：
1.出现唯一性约束问题：
com.jfinal.plugin.activerecord.ActiveRecordException: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Duplicate entry '075743725545' for key 'uq_user_account'
at com.jfinal.plugin.activerecord.Model.save(Model.java:413)
at com.ynwl.fengche.model.User.addUser(User.java:50)
at com.ynwl.fengche.service.UserService.userLogin(UserService.java:38)
at com.ynwl.fengche.service.UserService$$EnhancerByCGLIB$$2f96cee4.CGLIB$userLogin$5()
at com.ynwl.fengche.service.UserService$$EnhancerByCGLIB$$2f96cee4$$FastClassByCGLIB$$6c7e6394.invoke()
at net.sf.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228)
at com.jfinal.aop.Invocation.invoke(Invocation.java:82)
at com.jfinal.aop.Callback.intercept(Callback.java:96)
at com.ynwl.fengche.service.UserService$$EnhancerByCGLIB$$2f96cee4.userLogin()
at com.ynwl.fengche.controller.AuthController.index(AuthController.java:68)
at sun.reflect.GeneratedMethodAccessor125.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at com.jfinal.aop.Invocation.invoke(Invocation.java:73)
at com.ynwl.fengche.interceptor.AuthInterceptor.intercept(AuthInterceptor.java:40)
at com.jfinal.aop.Invocation.invoke(Invocation.java:67)
at com.jfinal.core.ActionHandler.handle(ActionHandler.java:74)
at com.jfinal.plugin.druid.DruidStatViewHandler.handle(DruidStatViewHandler.java:75)
at com.ynwl.fengche.controller.CommonHandler.handle(CommonHandler.java:17)
at com.jfinal.ext.handler.ContextPathHandler.handle(ContextPathHandler.java:47)
at com.jfinal.core.JFinalFilter.doFilter(JFinalFilter.java:72)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:218)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505)
at com.orangefunction.tomcat.redissessions.RedisSessionHandlerValve.invoke(RedisSessionHandlerValve.java:22)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:442)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1082)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:623)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)

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以上问题，重复报了几次了。但实际上有几个用户登录了。都出现这个账号约束错误。

疑问：
1.几个不同的账号登录，为什么还是这一个账号的约束性问题？
2.难道是连接池出现错误，没提交成功，会一直提交？

程序架构：jfianl2.2+druid1.0.26