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1. How to update data for a JPA many-to-many relationship?    java-forums.org

public void updateUserInfo(User user) throws NoSuchUserException, NoSuchProjectException { if (user == null || user.getId() == null) throw new IllegalArgumentException(); findUserByID(user.getId()); Set projects = user.getProjects(); Set members = null; if (projects != null) { for (Project p : projects) { members = p.getMembers(); if (members == null) { members = new HashSet() ; } members.add(user); p.setMembers(members); projectServiceLocal.updateProjectInfo(p); } } em.merge(user); }

2. Data retrieval of one-to-many relationship    forum.hibernate.org

Hi all, I have two entities which have one-to-many relationship. Lets say 'Course' and 'Student' One Course can have many number of students. Then in Course class there is a field like private List students = new ArrayList(); I want to know that when we get a particular Course object, is it come with relevant Students objects ? I think it ...

3. How can i Retrive Data from Many To Many Relationship    forum.hibernate.org

Hi All, I am new In Hibernate,i am facing problem in many to many relationship: Problem Is I have 3 tabels 1-book(book_id,book_name) 2-Publisher(Publisher_Id,Relaease_Date) 3-Book_Info(book_id,Publisher_Id) I want to display first two tabels data.then how can i create many to many relationship and retrive the data.tell me HBM file ,pojo file and DAO flow of code

4. Populating data for a one-to-one relationship    forum.hibernate.org

Hi, Newbie here. I am using Hibernate 2.0 for my project. My object structure is as follows. class User { long userId; String username; String password; User createBy; Timestamp createOn; User updateBy; Timestamp updateOn; } The corresponding database table structure is as follows (I am using SAPDB). USER USERID: Primary Key USERNAME PASSWORD CREATEBY: Foreign Key CREATEON UPDATEBY: Foreign Key UPDATEON ...

5. ONE-TO-ONE relationship with shared data from superclass    forum.hibernate.org

I'm retrofitting hibernate to a somewhat arcane table per sub-class, manual, pre-hibernate application. I've done this using subclasses, joins and discriminators. The outline of my problem is as follows: I have the superclass DiaryItem mapped to table DIARYITEM, primary key DIARYID A subclass of the DiaryItem, DiaryAction maps to table DIARYACTION, with its primary key DIARYID being the foreign key of ...

6. How to configure many-to-many w/ data on relationship    forum.hibernate.org

Hi all We need to configure a few many-to-many relationships in Hibernate. I believe I get the concept of a "simple" many-to-many relationship. However, I haven't found any examples on how to configure such a relationships if the many-to-many map itself contains data about the mapping. Say I have: Table INVOICE (ID, INVOICENUMBER, AMOUNT) Table PAYMENT (ID, PAYMENTDATE, AMOUNT) A many-to-many ...

7. Problem saving data with link table relationship...    forum.hibernate.org

I'm using Hibernate 3.x and created a fairly straight forward relationship. I have CUSTOMER, ADDRESS and LINK_CUST_ADDR tables. The LINK_CUST_ADDR table just defines a foreign key relationship to each of the other two tables so I can have a many-to-many relationship. I am using MyEclipseIDE's built in support for generation of the POJOs. They seem to have been generated correctly from ...