报错如下：

  1. org.springframework.orm.jpa.JpaObjectRetrievalFailureException: Unable to find com.rollong.chinatower.server.persistence.entity.staff.Department with id 0; nested exception is javax.persistence.EntityNotFoundException: Unable to find com.rollong.chinatower.server.persistence.entity.staff.Department with id 0
  2.     at org.springframework.orm.jpa.EntityManagerFactoryUtils.convertJpaAccessExceptionIfPossible(EntityManagerFactoryUtils.java:373)
  3.     at org.springframework.orm.jpa.vendor.HibernateJpaDialect.translateExceptionIfPossible(HibernateJpaDialect.java:227)
  4.     at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.translateExceptionIfPossible(AbstractEntityManagerFactoryBean.java:507)
  5.     at org.springframework.dao.support.ChainedPersistenceExceptionTranslator.translateExceptionIfPossible(ChainedPersistenceExceptionTranslator.java:61)
  6.     at org.springframework.dao.support.DataAccessUtils.translateIfNecessary(DataAccessUtils.java:242)
  7.     at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:153)
  8.     at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185)
  9.     at org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:135)
  10.     at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185)
  11.     at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
  12.     at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185)
  13.     at org.springframework.data.repository.core.support.SurroundingTransactionDetectorMethodInterceptor.invoke(SurroundingTransactionDetectorMethodInterceptor.java:61)
  14.     at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185)
  15.     at org.springframework.data.repository.core.support.MethodInvocationValidator.invoke(MethodInvocationValidator.java:99)
  16.     at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185)
  17.     at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212)
  18.     at com.sun.proxy.$Proxy169.findStaffByIdCard(Unknown Source)
  19.     at com.rollong.chinatower.server.service.staff.StaffExcelService.fromMap(StaffExcelService.kt:99)
  20.     at com.rollong.chinatower.server.service.staff.StaffExcelService.import(StaffExcelService.kt:56)
  21.     at com.rollong.chinatower.server.api.controller.staff.StaffController.import(StaffController.kt:254)
  22.     at com.rollong.chinatower.server.api.controller.staff.StaffController$$FastClassBySpringCGLIB$$549aa66f.invoke(<generated>)
  23.     at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
  24.     at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:747)
  25.     at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
  26.     at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:294)
  27.     at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98)
  28.     at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185)
  29.     at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:689)
  30.     at com.rollong.chinatower.server.api.controller.staff.StaffController$$EnhancerBySpringCGLIB$$b241735f.import(<generated>)
  31.     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  32.     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
  33.     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  34.     at java.lang.reflect.Method.invoke(Method.java:498)
  35.     at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209)
  36.     at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136)
  37.     at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102)
  38.     at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:870)
  39.     at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:776)
  40.     at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
  41.     at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991)
  42.     at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925)
  43.     at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:978)
  44.     at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:881)
  45.     at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
  46.     at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:855)
  47.     at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
  48.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
  49.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
  50.     at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
  51.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
  52.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
  53.     at com.rollong.chinatower.server.security.CORSFilter.doFilter(CORSFilter.kt:19)
  54.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
  55.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
  56.     at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:158)
  57.     at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:126)
  58.     at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:111)
  59.     at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
  60.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
  61.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
  62.     at com.alibaba.druid.support.http.WebStatFilter.doFilter(WebStatFilter.java:123)
  63.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
  64.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
  65.     at org.springframework.boot.actuate.web.trace.servlet.HttpTraceFilter.doFilterInternal(HttpTraceFilter.java:84)
  66.     at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
  67.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
  68.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
  69.     at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:320)
  70.     at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127)
  71.     at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91)
  72.     at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
  73.     at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:119)
  74.     at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
  75.     at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137)
  76.     at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
  77.     at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111)
  78.     at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
  79.     at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:170)
  80.     at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
  81.     at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63)
  82.     at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
  83.     at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:116)
  84.     at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
  85.     at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:66)
  86.     at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
  87.     at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
  88.     at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105)
  89.     at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
  90.     at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56)
  91.     at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
  92.     at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
  93.     at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:215)
  94.     at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:178)
  95.     at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:357)
  96.     at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:270)
  97.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
  98.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
  99.     at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)
  100.     at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
  101.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
  102.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
  103.     at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:109)
  104.     at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
  105.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
  106.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
  107.     at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81)
  108.     at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
  109.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
  110.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
  111.     at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)
  112.     at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
  113.     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
  114.     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
  115.     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199)
  116.     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
  117.     at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496)
  118.     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
  119.     at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
  120.     at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
  121.     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
  122.     at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803)
  123.     at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
  124.     at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790)
  125.     at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459)
  126.     at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
  127.     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
  128.     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
  129.     at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
  130.     at java.lang.Thread.run(Thread.java:748)
  131. Caused by: javax.persistence.EntityNotFoundException: Unable to find com.rollong.chinatower.server.persistence.entity.staff.Department with id 0
  132.     at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$JpaEntityNotFoundDelegate.handleEntityNotFound(EntityManagerFactoryBuilderImpl.java:159)
  133.     at org.hibernate.event.internal.DefaultLoadEventListener.load(DefaultLoadEventListener.java:227)
  134.     at org.hibernate.event.internal.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:262)
  135.     at org.hibernate.event.internal.DefaultLoadEventListener.doOnLoad(DefaultLoadEventListener.java:121)
  136.     at org.hibernate.event.internal.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:89)
  137.     at org.hibernate.internal.SessionImpl.fireLoad(SessionImpl.java:1239)
  138.     at org.hibernate.internal.SessionImpl.internalLoad(SessionImpl.java:1122)
  139.     at org.hibernate.type.EntityType.resolveIdentifier(EntityType.java:672)
  140.     at org.hibernate.type.EntityType.resolve(EntityType.java:457)
  141.     at org.hibernate.engine.internal.TwoPhaseLoad.doInitializeEntity(TwoPhaseLoad.java:165)
  142.     at org.hibernate.engine.internal.TwoPhaseLoad.initializeEntity(TwoPhaseLoad.java:125)
  143.     at org.hibernate.loader.Loader.initializeEntitiesAndCollections(Loader.java:1152)
  144.     at org.hibernate.loader.Loader.processResultSet(Loader.java:1011)
  145.     at org.hibernate.loader.Loader.doQuery(Loader.java:949)
  146.     at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:341)
  147.     at org.hibernate.loader.Loader.doList(Loader.java:2692)
  148.     at org.hibernate.loader.Loader.doList(Loader.java:2675)
  149.     at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2507)
  150.     at org.hibernate.loader.Loader.list(Loader.java:2502)
  151.     at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:502)
  152.     at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:392)
  153.     at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:216)
  154.     at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1489)
  155.     at org.hibernate.query.internal.AbstractProducedQuery.doList(AbstractProducedQuery.java:1445)
  156.     at org.hibernate.query.internal.AbstractProducedQuery.list(AbstractProducedQuery.java:1414)
  157.     at org.hibernate.query.Query.getResultList(Query.java:146)
  158.     at org.hibernate.query.criteria.internal.compile.CriteriaQueryTypeQueryAdapter.getResultList(CriteriaQueryTypeQueryAdapter.java:72)
  159.     at org.springframework.data.jpa.repository.query.JpaQueryExecution$CollectionExecution.doExecute(JpaQueryExecution.java:129)
  160.     at org.springframework.data.jpa.repository.query.JpaQueryExecution.execute(JpaQueryExecution.java:91)
  161.     at org.springframework.data.jpa.repository.query.AbstractJpaQuery.doExecute(AbstractJpaQuery.java:136)
  162.     at org.springframework.data.jpa.repository.query.AbstractJpaQuery.execute(AbstractJpaQuery.java:125)
  163.     at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:590)
  164.     at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:578)
  165.     at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185)
  166.     at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:59)
  167.     at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185)
  168.     at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:294)
  169.     at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98)
  170.     at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185)
  171.     at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:139)
  172.     ... 123 more

解决方法：

第一种：由于后来加上的实体、对象在之前的数据没有关联上，所以造成脏数据、故根本的解决方法，就是将之前的测试数据删除，重新添加数据就行了

第二种：

1. 检查为什么子表中没有主表中ID对应的记录

2. 如果子表中没有主表ID对应的记录也可以正常加载数据，那么需要在主表字段上加一个@NotFound Annotation。示例如下：

@OneToOne(optional=false)
    @JoinColumn(name="business_id")
    @NotFound(action=NotFoundAction.IGNORE)
    private Business business;

这样，当子表中没找到数据时，主表中对应的field就是null，而不会报错了。

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