Hi to all! I am a beginner in Hibernate and right now I am on the task of deleting a particular entity("Employee")
but upon deleting it the entities(empPassport, empPic, empAttachment, & empWorkExperience) which are collections
inside the said entity must also be deleted(delete-cascade).

In order to do this here is my Employee.hbm.xml mapping file:

<hibernate-mapping>
<class name="Employee" table="employee">
<id name="empId" column="employee_id" type="java.lang.Integer" >
<generator class="identity"/>
</id>

<!--PROPERTIES HERE-->
<property/>
...
<property/>

<!--Mapping for Set EmployeePassport-->
<set name="empPassport" inverse="true" lazy="true" cascade="delete">
<key column="employee_id" not-null="true"/>
<one-to-many class="EmployeePassport"/>
</set>

<!--Mapping for Set EmployeeWorkExperience-->
<set name="empWorkExp" inverse="true" lazy="true" cascade="delete">
<key column="employee_id" not-null="true"/>
<one-to-many class="EmployeeWorkExperience"/>
</set>

<!--Mapping for Set EmployeeAttachment-->
<set name="empAttachment" inverse="true" lazy="true" cascade="delete">
<key column="employee_id" not-null="true"/>
<one-to-many class="EmployeeAttachment"/>
</set>

<!--Mapping for EmployeePicture-->
<one-to-one name="empPic" class="EmployeePicture" cascade="delete"/>
</class>
</hibernate-mapping>

To further explain, as can be seen with my mapping for my class "Employee" which is to be persisted to table "employee",
I am trying to delete the employee records and at the same time delete all other records(empPassport, empPicture, empAttachment,
& empWorkExp) which is technically known as delete-cascade. These aformentioned records are collections inside "Employee". After building
and starting the tomcat all things are good meaning i have no error but upon hitting the delete button in my webpage causing
the invocation of delete function I now have this stack trace warnings and errors:

2006-08-09 16:42:00,368 WARN - JDBCExceptionReporter.logExceptions(71) | SQL Error: 1451, SQLState: 23000
2006-08-09 16:42:00,368 ERROR - JDBCExceptionReporter.logExceptions(72) | Cannot delete or update a parent row: a foreign key constraint fails (`eportal3/employee_passport`, CONSTRAINT `FKF2967A831229D0E0` FOREIGN KEY (`employee_id`) REFERENCES `employee` (`employee_id`))
2006-08-09 16:42:00,378 ERROR - AbstractFlushingEventListener.performExecutions(299) | Could not synchronize database state with session
org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:69)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:202)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:230)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:145)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:296)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:27)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:980)
at com.exist.eportal.dao.hibernate.EmployeeDaoImpl.removeEmployee(EmployeeDaoImpl.java:88)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:287)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:181)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:148)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:170)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:176)
at $Proxy2.removeEmployee(Unknown Source)
at com.exist.eportal.employee.db.DBPimService.deleteEmployee(DBPimService.java:176)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:287)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:165)
at $Proxy6.deleteEmployee(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at uk.ltd.getahead.dwr.impl.ExecuteQuery.execute(ExecuteQuery.java:170)
at uk.ltd.getahead.dwr.impl.DefaultProcessor.doExec(DefaultProcessor.java:552)
at uk.ltd.getahead.dwr.impl.DefaultProcessor.handle(DefaultProcessor.java:88)
at uk.ltd.getahead.dwr.DWRServlet.doPost(DWRServlet.java:178)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:292)
at org.acegisecurity.intercept.web.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:116)
at org.acegisecurity.intercept.web.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:79)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:303)
at org.acegisecurity.ui.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:143)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:303)
at org.acegisecurity.providers.anonymous.AnonymousProcessingFilter.doFilter(AnonymousProcessingFilter.java:138)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:303)
at org.acegisecurity.wrapper.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:50)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:303)
at org.acegisecurity.securechannel.ChannelProcessingFilter.doFilter(ChannelProcessingFilter.java:168)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:303)
at org.acegisecurity.ui.rememberme.RememberMeProcessingFilter.doFilter(RememberMeProcessingFilter.java:174)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:303)
at org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:246)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:303)
at org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:220)
at org.acegisecurity.util.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:303)
at org.acegisecurity.util.FilterChainProxy.doFilter(FilterChainProxy.java:173)
at org.acegisecurity.util.FilterToBeanProxy.doFilter(FilterToBeanProxy.java:120)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.opensymphony.module.sitemesh.filter.PageFilter.doFilter(PageFilter.java:39)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.exist.eportal.web.filter.MessageFilter.doFilter(MessageFilter.java:33)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:174)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:214)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:198)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:152)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:137)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:118)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:102)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:929)
at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:160)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:799)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:705)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:577)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
at java.lang.Thread.run(Thread.java:534)
Caused by: java.sql.BatchUpdateException: Cannot delete or update a parent row: a foreign key constraint fails (`eportal3/employee_passport`, CONSTRAINT `FKF2967A831229D0E0` FOREIGN KEY (`employee_id`) REFERENCES `employee` (`employee_id`))
at com.mysql.jdbc.ServerPreparedStatement.executeBatch(ServerPreparedStatement.java:648)
at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:58)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:195)
... 91 more

I hope someone has encountered(even if not as long as he can give me suggestions/solutions) the same experience and post a solution to this. Tnx!

Note: "employee_id" is the primary key of table employee and foreign key to the these tables-> employee_attachment,
employee_passport, and employee_work_experience.

did you can try cascade="all-delete-orphan" on <set> element

I did try your suggestion bkmr_77 but I am still getting the same error. Tnx anyway!:)

original:
<set name="empPassport" inverse="true" lazy="true" cascade="delete">
new:
<set name="empPassport" inverse="false" lazy="true" cascade="delete">

In many scenarios, I found that I can't rely on ORM cascading delete.
Since Hibernate does not take care the association management when setting up a new one ( you have to write the code at both side), how can we rely on it to remove one?