Article article = new Article();
		article.setName("test");
		List<Section> articles = article.getSections(); //ArrayList
		Section section1 = new Section();
		section1.setName("test");
		section1.setContent("test");
		articles.add(section1);
		Section section2 = new Section();
		section2.setName("test");
		section2.setContent("test");
		articles.add(section2);
		Section section3 = new Section();
		section3.setName("test");
		section3.setContent("test");
		articles.add(section3);
		session.save(article);  //throw exception here

		Article article = articleManager.get(1L);
		article.setName("test");
		List<Section> articles = new ArrayList<Section>();
		Section section1 = new Section();
		section1.setName("test");
		section1.setContent("test");
		articles.add(section1);
		Section section2 = new Section();
		section2.setName("test");
		section2.setContent("test");
		articles.add(section2);
		Section section3 = new Section();
		section3.setName("test");
		section3.setContent("test");
		articles.add(section3);
		article.setSections(sections);
		session.save(article);  //throw exception here

		Article article = articleManager.get(1L);
		article.setName("test");
		List<Section> articles = article.getSections(); //PersistentList
		articles.clear();
		Section section1 = new Section();
		section1.setName("test");
		section1.setContent("test");
		articles.add(section1);
		Section section2 = new Section();
		section2.setName("test");
		section2.setContent("test");
		articles.add(section2);
		Section section3 = new Section();
		section3.setName("test");
		section3.setContent("test");
		articles.add(section3);
		session.save(article);  // it works fine

org.hibernate.jdbc.BatchedTooManyRowsAffectedException: Batch update returned unexpected row count from update [0]; actual row count: 3; expected: 1