@Entity(name = "Ppv")
  @Table(name = "PPV")
  public static class Ppv {

    @Id
    Long ppvId;
    
    @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER, mappedBy = "ppv", orphanRemoval = true)
    Set<Uvazek> uvazeks = new HashSet<Uvazek>(0);
    
  }

@Entity(name = "Uvazek")
  @Table(name = "UVAZEK")
  public static class Uvazek {
    
    @Id
    Long uvazekId;
    
    @ManyToOne
    @JoinColumn(name = "PPV_FXID")
    Ppv ppv;

  }

Ppv ppv = (Ppv) getSession().get(Ppv.class, 1l);

    getSession().clear();
    
    ppv.uvazeks.remove(ppv.uvazeks.iterator().next());
    getSession().merge(ppv);
    getSession().flush();
    
    getSession().clear();
    
    ppv.uvazeks.remove(ppv.uvazeks.iterator().next());
    getSession().merge(ppv);
    //this flush cause exception
    getSession().flush();

org.hibernate.ObjectNotFoundException: No row with the given identifier exists: [test.hibernate.TestPrepravkaOsobaSAdresou$Uvazek#2]
	at org.hibernate.internal.SessionFactoryImpl$1$1.handleEntityNotFound(SessionFactoryImpl.java:244)
	at org.hibernate.event.internal.DefaultLoadEventListener.load(DefaultLoadEventListener.java:212)
	at org.hibernate.event.internal.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:262)
	at org.hibernate.event.internal.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:150)
	at org.hibernate.internal.SessionImpl.fireLoad(SessionImpl.java:1098)
	at org.hibernate.internal.SessionImpl.internalLoad(SessionImpl.java:1025)
	at org.hibernate.type.EntityType.resolveIdentifier(EntityType.java:671)
	at org.hibernate.type.EntityType.resolve(EntityType.java:489)
	at org.hibernate.type.EntityType.replace(EntityType.java:353)
	at org.hibernate.type.CollectionType.preserveSnapshot(CollectionType.java:580)
	at org.hibernate.type.CollectionType.replaceElements(CollectionType.java:532)
	at org.hibernate.type.CollectionType.replace(CollectionType.java:660)
	at org.hibernate.type.TypeHelper.replace(TypeHelper.java:177)
	at org.hibernate.event.internal.DefaultMergeEventListener.copyValues(DefaultMergeEventListener.java:372)
	at org.hibernate.event.internal.DefaultMergeEventListener.entityIsDetached(DefaultMergeEventListener.java:309)
	at org.hibernate.event.internal.DefaultMergeEventListener.onMerge(DefaultMergeEventListener.java:151)
	at org.hibernate.event.internal.DefaultMergeEventListener.onMerge(DefaultMergeEventListener.java:76)
	at org.hibernate.internal.SessionImpl.fireMerge(SessionImpl.java:914)
	at org.hibernate.internal.SessionImpl.merge(SessionImpl.java:898)
	at org.hibernate.internal.SessionImpl.merge(SessionImpl.java:902)
	at test.hibernate.TestPrepravkaOsobaSAdresou.testSessionGet(TestPrepravkaOsobaSAdresou.java:90)
	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:597)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:45)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:42)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
	at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
	at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:74)
	at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:83)
	at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:72)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:231)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:47)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:231)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:60)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:229)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:50)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:222)
	at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
	at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:71)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:300)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:174)
	at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:49)
	at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)