ShardingSphere跨表查询报错

目录

    • 一、场景简介
    • 二、报错信息
    • 三、SQL
    • 四、原因
    • 五、解决
      • 方法一、调整SQL，不使用子查询
      • 方法二、将子查询的SQL独立出来，后续连接逻辑由代码处理

一、场景简介

1、使用ShardingSphere按月份进行分表

2、单月查询正常（单表）

3、跨月查询报错（跨表）

二、报错信息

### Error querying database.  Cause: java.lang.NullPointerException
### The error may exist in file [/home/xxx/devtest/robot/robot-admin-8073/webapps/RobotManagerSvr/WEB-INF/classes/mappings/RobotQuestionMapper.xml]
### The error may involve com.xxx.mapper.RobotQuestionMapper.getQuestionReportList
### The error occurred while handling results
### SQL: SELECT   t1.quesId,   t1.questionMsg,   t2.qName AS questionType,   count( t4.sId ) AS satCount,   count( t4.flag = '1' OR NULL ) AS solveCount,   count( t4.flag = '0' OR NULL ) AS unSolveCount,   ROUND(IFNULL(count( t4.flag = '1' OR NULL ) / count( t4.sId ), 0) * 100, 2) AS solvePercent,         t6.browseQty   FROM   t_robot_question AS t1   LEFT JOIN t_robot_questiontype AS t2 ON t1.qId = t2.qId   LEFT JOIN t_robot_messageReplay AS t3 ON t1.quesId = t3.quesId   LEFT JOIN t_robot_SolveRec AS t4 ON t3.recId = t4.recId   LEFT JOIN t_robot_sessionmsg AS t5 ON t3.SessionID = t5.SessionID   LEFT JOIN (             SELECT quesId, sum(IFNULL( hitQty, 0 )) AS browseQty             FROM t_robot_ques_statistics4ques             WHERE companyId = ? GROUP BY quesId         ) AS t6 ON t1.quesId = t6.quesId   WHERE   t1.companyId = ?   AND t3.CreateTime BETWEEN ? AND ?           GROUP BY   t1.quesId,   t1.questionMsg,   t2.qName         HAVING t1.quesId IS NOT NULL   ORDER BY t3.CreateTime DESC
### Cause: java.lang.NullPointerException
org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: java.lang.NullPointerException
### The error may exist in file [/home/xxx/devtest/robot/robot-admin-8073/webapps/RobotManagerSvr/WEB-INF/classes/mappings/RobotQuestionMapper.xml]
### The error may involve com.xxx.mapper.RobotQuestionMapper.getQuestionReportList
### The error occurred while handling results
### SQL: SELECT   t1.quesId,   t1.questionMsg,   t2.qName AS questionType,   count( t4.sId ) AS satCount,   count( t4.flag = '1' OR NULL ) AS solveCount,   count( t4.flag = '0' OR NULL ) AS unSolveCount,   ROUND(IFNULL(count( t4.flag = '1' OR NULL ) / count( t4.sId ), 0) * 100, 2) AS solvePercent,         t6.browseQty   FROM   t_robot_question AS t1   LEFT JOIN t_robot_questiontype AS t2 ON t1.qId = t2.qId   LEFT JOIN t_robot_messageReplay AS t3 ON t1.quesId = t3.quesId   LEFT JOIN t_robot_SolveRec AS t4 ON t3.recId = t4.recId   LEFT JOIN t_robot_sessionmsg AS t5 ON t3.SessionID = t5.SessionID   LEFT JOIN (             SELECT quesId, sum(IFNULL( hitQty, 0 )) AS browseQty             FROM t_robot_ques_statistics4ques             WHERE companyId = ? GROUP BY quesId         ) AS t6 ON t1.quesId = t6.quesId   WHERE   t1.companyId = ?   AND t3.CreateTime BETWEEN ? AND ?           GROUP BY   t1.quesId,   t1.questionMsg,   t2.qName         HAVING t1.quesId IS NOT NULL   ORDER BY t3.CreateTime DESC
### Cause: java.lang.NullPointerException
	at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:77)
	at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:446)
	at com.sun.proxy.$Proxy99.selectList(Unknown Source)
	at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:230)
	at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:137)
	at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:75)
	at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:59)
	at com.sun.proxy.$Proxy161.getQuestionReportList(Unknown Source)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:343)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:198)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
	at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:139)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
	at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212)
	at com.sun.proxy.$Proxy162.getQuestionReportList(Unknown Source)
	at com.xxx.service.Impl.RobotQuestionServiceImpl.getQuestionReportList(RobotQuestionServiceImpl.java:656)
	at com.xxx.service.Impl.RobotQuestionServiceImpl$$FastClassBySpringCGLIB$$41e86926.invoke(<generated>)
	at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)
	at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:684)
	at com.xxx.service.Impl.RobotQuestionServiceImpl$$EnhancerBySpringCGLIB$$37dbcb67.getQuestionReportList(<generated>)
	at com.xxx.controller.RobotQuestionController.getQuestionReportList(RobotQuestionController.java:1094)
	at com.xxx.controller.RobotQuestionController$$FastClassBySpringCGLIB$$abadd88e.invoke(<generated>)
	at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)
	at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:749)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
	at org.springframework.aop.framework.adapter.AfterReturningAdviceInterceptor.invoke(AfterReturningAdviceInterceptor.java:55)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:175)
	at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:93)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
	at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:688)
	at com.xxx.controller.RobotQuestionController$$EnhancerBySpringCGLIB$$a3088a72.getQuestionReportList(<generated>)
	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:498)
	at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:189)
	at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:800)
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1038)
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942)
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005)
	at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:908)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:101)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at com.xxx.filter.XssFilter.doFilter(XssFilter.java:53)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:320)
	at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127)
	at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91)
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
	at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:119)
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
	at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137)
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
	at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111)
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
	at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:170)
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
	at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63)
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
	at com.xxx.jwt.JwtAuthenticationTokenFilter.doFilterInternal(JwtAuthenticationTokenFilter.java:145)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
	at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:116)
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
	at org.springframework.web.filter.CorsFilter.doFilterInternal(CorsFilter.java:96)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
	at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:74)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
	at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105)
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
	at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
	at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:215)
	at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:178)
	at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:357)
	at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:270)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at org.springframework.boot.web.servlet.support.ErrorPageFilter.doFilter(ErrorPageFilter.java:130)
	at org.springframework.boot.web.servlet.support.ErrorPageFilter.access$000(ErrorPageFilter.java:66)
	at org.springframework.boot.web.servlet.support.ErrorPageFilter$1.doFilterInternal(ErrorPageFilter.java:105)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.springframework.boot.web.servlet.support.ErrorPageFilter.doFilter(ErrorPageFilter.java:123)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:94)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
	at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:620)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:502)
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1132)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:684)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1539)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1495)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:750)

三、SQL

<select id="getQuestionReportList" resultType="com.alibaba.fastjson.JSONObject">
	SELECT
	t1.quesId,
	t1.questionMsg,
	t2.qName AS questionType,
	count( t4.sId ) AS satCount,
	count( t4.flag = '1' OR NULL ) AS solveCount,
	count( t4.flag = '0' OR NULL ) AS unSolveCount,
	ROUND(IFNULL(count( t4.flag = '1' OR NULL ) / count( t4.sId ), 0) * 100, 2) AS solvePercent,
    t6.browseQty
	FROM
	t_robot_question AS t1
	LEFT JOIN t_robot_questiontype AS t2 ON t1.qId = t2.qId
	LEFT JOIN t_robot_messageReplay AS t3 ON t1.quesId = t3.quesId
	LEFT JOIN t_robot_SolveRec AS t4 ON t3.recId = t4.recId
	LEFT JOIN t_robot_sessionmsg AS t5 ON t3.SessionID = t5.SessionID
    LEFT JOIN (
        SELECT quesId, sum(IFNULL( hitQty, 0 )) AS browseQty
        FROM t_robot_ques_statistics4ques
        WHERE companyId = #{companyId} GROUP BY quesId
    ) AS t6 ON t1.quesId = t6.quesId
	WHERE
	t1.companyId = #{companyId}
	AND t3.CreateTime BETWEEN #{beginDate} AND #{endDate}
	AND t4.CreateTime BETWEEN #{beginDate} AND #{endDate}
	AND t5.CreateTime BETWEEN #{beginDate} AND #{endDate}
	GROUP BY
	t1.quesId,
	t1.questionMsg,
	t2.qName
	ORDER BY t3.CreateTime DESC
</select>

四、原因

是子查询的导致（具体原因不明）

在这里插入图片描述

五、解决

方法一、调整SQL，不使用子查询

方法二、将子查询的SQL独立出来，后续连接逻辑由代码处理

1、去除子查询

在这里插入图片描述

2、将子查询封装为mapp方法

在这里插入图片描述

3、由代码完成连接

在这里插入图片描述

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