当我要求hibernate更新父记录时，为什么hibernate要删除子记录？
以这个映射文件为例当我要求hibernate更新父记录时，为什么hibernate要删除子记录？,hibernate,Hibernate,以这个映射文件为例 <class name="com.data.StudentData" table="gr_student"> <id name="id"> <generator class="identity" /> </id> <property name="studentYear" column="student_year"/&g
<class name="com.data.StudentData"
table="gr_student">
<id name="id">
<generator class="identity" />
</id>
<property name="studentYear" column="student_year"/>
<property name="programId" column="program_id"/>
<property name="firstName" column="first_name"/>
<property name="lastName" column="last_name"/>
...
snip
...
<property name="testUser" column="testuser"/>
<property name="currentMailing" column="current_mailing"/>
<property name="updated"/>
<property name="inScholarHistoryQueue" column="in_scholar_history_queue"/>
<property name="mailUndeliverable"
column="mail_undeliverable"
insert="false"/>
<bag name="responses"
table="gr_response"
batch-size="200"
lazy="false">
<key column="student_id"/>
<one-to-many class="parity.data.ResponseData"/>
</bag>
</class>
...
剪
...
2011-07-13 01:20:24,464 [http-bio-/10.99.2.17-8080-exec-54] ERROR org.hibernate.util.JDBCExceptionReporter - ERROR: null value in column "student_id" violates not-null constraint
2011-07-13 01:20:24,465 [http-bio-/10.99.2.17-8080-exec-54] DEBUG org.springframework.orm.hibernate3.HibernateTransactionManager - Initiating transaction rollback after commit exception
org.springframework.dao.DataIntegrityViolationException: could not delete collection: [parity.data.StudentData.responses#744589]; SQL [update ogr.gr_response set student_id=null where student_id=?]; constraint [null]; nested exception is org.hibernate.exception.ConstraintViolationException: could not delete collection: [parity.data.StudentData.responses#744589]
at org.springframework.orm.hibernate3.SessionFactoryUtils.convertHibernateAccessException(SessionFactoryUtils.java:637)
at org.springframework.orm.hibernate3.HibernateTransactionManager.convertHibernateAccessException(HibernateTransactionManager.java:793)
at org.springframework.orm.hibernate3.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:664)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:754)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:723)
at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:393)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:120)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedInterceptor.intercept(Cglib2AopProxy.java:621)
at parity.persistence.DataAccess$$EnhancerByCGLIB$$bac52431.runTransaction(<generated>)
at parity.model.Student.queueScholarHistoryUpdates(Student.java:984)
at parity.model.Student$$FastClassByCGLIB$$c0537c95.invoke(<generated>)
at net.sf.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
at org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedInterceptor.intercept(Cglib2AopProxy.java:617)
at parity.model.Student$$EnhancerByCGLIB$$c7a2254e.queueScholarHistoryUpdates(<generated>)
at parity.action.StudentDataSyncAction.queueScholarHistoryUpdates(StudentDataSyncAction.java:36)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:48)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37)
at java.lang.reflect.Method.invoke(Method.java:600)
at com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:440)
at com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:279)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:163)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:251)
at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:122)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:148)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:94)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:243)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:89)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:128)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:270)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:126)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:138)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:164)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:128)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:176)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52)
at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:498)
at org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:434)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at com.nmscsys.util.AuthenticationFilterAdmin.doFilter(AuthenticationFilterAdmin.java:91)
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:224)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:405)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:964)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:515)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:736)
Caused by: org.hibernate.exception.ConstraintViolationException: could not delete collection: [parity.data.StudentData.responses#744589]
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:96)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
at org.hibernate.persister.collection.AbstractCollectionPersister.remove(AbstractCollectionPersister.java:1131)
at org.hibernate.action.CollectionRemoveAction.execute(CollectionRemoveAction.java:107)
at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:273)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:265)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:186)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:51)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1216)
at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:383)
at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:133)
at org.springframework.orm.hibernate3.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:656)
... 84 more
Caused by: java.sql.BatchUpdateException: Batch entry 0 update ogr.gr_response set student_id=null where student_id='717804' was aborted. Call getNextException to see the cause.
at org.postgresql.jdbc2.AbstractJdbc2Statement$BatchResultHandler.handleError(AbstractJdbc2Statement.java:2598)
at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1836)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:407)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeBatch(AbstractJdbc2Statement.java:2737)
at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:70)
at org.hibernate.jdbc.BatchingBatcher.addToBatch(BatchingBatcher.java:56)
at org.hibernate.persister.collection.AbstractCollectionPersister.remove(AbstractCollectionPersister.java:1108)
... 94 more
2011-07-13 01:20:24464[http bio-/10.99.2.17-8080-exec-54]ERROR org.hibernate.util.jdbceptionReporter-错误：“学生id”列中的空值违反了非空约束
2011-07-13 01:20:24465[http bio-/10.99.2.17-8080-exec-54]调试org.springframework.orm.hibernate3.HibernateTransactionManager-在提交异常后启动事务回滚
org.springframework.dao.DataIntegrityViolationException:无法删除集合：[parity.data.StudentData.responses#744589]；SQL[更新ogr.gr_响应集student_id=null，其中student_id=？]；约束[null]；嵌套异常为org.hibernate.exception.ConstraintViolationException:无法删除集合：[parity.data.StudentData.responses#744589]
位于org.springframework.orm.hibernate3.SessionFactoryUtils.convertHibernateAccessException（SessionFactoryUtils.java:637）
位于org.springframework.orm.hibernate3.HibernateTransactionManager.convertHibernateAccessException（HibernateTransactionManager.java:793）
位于org.springframework.orm.hibernate3.HibernateTransactionManager.doCommit（HibernateTransactionManager.java:664）
位于org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit（AbstractPlatformTransactionManager.java:754）
位于org.springframework.transaction.support.AbstractPlatformTransactionManager.commit（AbstractPlatformTransactionManager.java:723）
位于org.springframework.transaction.interceptor.TransactionSpectSupport.commitTransactionAfterReturning（TransactionSpectSupport.java:393）
位于org.springframework.transaction.interceptor.TransactionInterceptor.invoke（TransactionInterceptor.java:120）
位于org.springframework.aop.framework.ReflectiveMethodInvocation.procedue（ReflectiveMethodInvocation.java:172）
位于org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedInterceptor.intercept（Cglib2AopProxy.java:621）
在parity.persistence.DataAccess$$enhancerbyglib$$bac52431.runTransaction（）处
at parity.model.Student.QueueScholarHistoryUpdate（Student.java:984）
在parity.model.Student$$FastClassByCGLIB$$c0537c95.invoke（）处
net.sf.cglib.proxy.MethodProxy.invoke（MethodProxy.java:204）
位于org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedInterceptor.intercept（Cglib2AopProxy.java:617）
at parity.model.Student$$enhancerbyglib$$c7a2254e.queueScholarHistoryUpdates（）
在parity.action.StudentDataSyncAction.queueScholarHistoryUpdates（StudentDataSyncAction.java:36）
在sun.reflect.NativeMethodAccessorImpl.invoke0（本机方法）处
在sun.reflect.NativeMethodAccessorImpl.invoke（NativeMethodAccessorImpl.java:48）中
在sun.reflect.DelegatingMethodAccessorImpl.invoke（DelegatingMethodAccessorImpl.java:37）中
位于java.lang.reflect.Method.invoke（Method.java:600）
在com.opensymphony.xwork2.DefaultActionInvocation.invokeAction（DefaultActionInvocation.java:440）
位于com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly（DefaultActionInvocation.java:279）
位于com.opensymphony.xwork2.DefaultActionInvocation.invoke（DefaultActionInvocation.java:242）
在com.opensymphony.xwork2.intercept.DefaultWorkflowIntercept.doIntercept（DefaultWorkflowIntercept.java:163）
在com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept（MethodFilterInterceptor.java:87）
位于com.opensymphony.xwork2.DefaultActionInvocation.invoke（DefaultActionInvocation.java:236）
位于com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept（ValidationInterceptor.java:251）
位于org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept（AnnotationValidationInterceptor.java:68）
在com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept（MethodFilterInterceptor.java:87）
位于com.opensymphony.xwork2.DefaultActionInvocation.invoke（DefaultActionInvocation.java:236）
在com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept上（ConversionErrorInterceptor.java:122）
位于com.opensymphony.xwork2.DefaultActionInvocation.invoke（DefaultActionInvocation.java:236）
在com.opensymphony.xwork2.interceptor.parameters-sinterceptor.doIntercept（parameters-sinterceptor.java:195）
在com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept（MethodFilterInterceptor.java:87）
位于com.opensymphony.xwork2.DefaultActionInvocation.invoke（DefaultActionInvocation.java:236）
在com.opensymphony.xwork2.interceptor.parameters-sinterceptor.doIntercept（parameters-sinterceptor.java:195）
在com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept（MethodFilterInterceptor.java:87）
位于com.opensymphony.xwork2.DefaultActionInvocation.invoke（DefaultActionInvocation.java:236）
在com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept上（StaticParametersInterceptor.java:148）
位于com.opensymphony.xwork2.DefaultActionInvocation.invoke（DefaultActionInvocation.java:236）
位于org.apache.struts2.interceptor.MultiselectInterceptor.intercept（MultiselectInterceptor.java:75）
位于com.opensymphony.xwork2.DefaultActionInvocation.invoke（DefaultActionInvocation.java:236）
位于org.apache.struts2.interceptor.CheckboxInterceptor.intercept（CheckboxInterceptor.java:94）
位于com.opensymphony.xwork2.DefaultActionInvocation.invoke（DefaultActionInvocation.java:236）
位于org.apache.struts2.interceptor.FileUploadInterceptor.intercept（FileUploadInterceptor.java:243）
在com.opensymphony.xwork2.DefaultActionInvocation.invoke（DefaultActionInvocati