association « Composite « JPA Q&A





1. How do I map a many-to-one association in Hibernate where the child has a composite key and a part of that is the primary key in the parent?    stackoverflow.com

I have a (legacy) table structure that looks a little bit like this:

table parent (
  parentid int (PK)
  ...
)

table child (
  parentid int (PK)
  childid int (PK)
 ...

2. traversing associations in composite pk using criteria    forum.hibernate.org

class A2B{ [..] public static class A_TO_B_ID implements Serializable { @ManyToOne private A a; @ManyToOne private B b; } public A getA(){ return a; } public setA(A a){ this.a = a; } private String str; public String getStr(){ return str; } public void setStr(String str){ this.str = str; } } [..] @EmbeddedId private A_TO_B_ID pk; @Transient public A getA(){ return pk.a; ...

4. need help: ternary association using composite-element    forum.hibernate.org

Hibernate version: 2.1.6 Hi All, I am struggling with the ternary association. Here is my model: * a department has many Programs * each program is associated with a set of Roles. for example: Program Manager, Program Member, etc. each program can have a different set of Roles. * User can participate in multiple Programs with a set of different Roles ...

5. composite one to one association    forum.hibernate.org

Consider the following example: Class Item has composite one to one association with class ItemLog directed to Item. I.e. Item knows _nothing_ about its ItemLog ItemLog know about it's Item There could be more that one ItemLog associated with single Item. When Item deleted from database I want ItemLog's to be deleted too. How can I implement it with hibernate without ...

6. MANY-TO-ONE Association with composite keys....???    forum.hibernate.org

Hi, I still have problems to model associations between tables with composite keys....HOW CAN I MODEL A MANY-TO-ONE ASSOCIATION TO A TABLE WITH COMPOSITE-ID???????????????????????????? I have the following tables: table Question question_id (pk) question_text table Option option_id (pk) question_id (pk and fk referencing table Question) table Vote vote_id (pk) option_id (fk to table Option) question_id (fk to table Option) According to ...

7. 1:n association with composite keys    forum.hibernate.org

thanks for the reply... how can i do that ? until now i always worked with primary keys, and not with composite keys. how can i tell hibernate to fetch all task where those two columns are equal ? do you have an example ? could you post some xml for me ? thanks for your help ! Jens

9. composite-id and association to tables with simple id    forum.hibernate.org

Newbie Joined: Thu Mar 31, 2005 4:15 am Posts: 4 I've got a problem. I can't bind two tables. In one ( parameter ) I've got composite-id. All parameters with the same RESID have the same paths ( they can have more then one path ). They can have diferent versions but all with the same RESID have one path. Secound ...





10. composite primary key associations    forum.hibernate.org

Hibernate version: 3.03 Hi Guys, Is it possible to define a composite primary key association? I know that I can do this using a simple key. I have a class Foo that has a composite primary key of the form: Foo composes another object called Bar. In the DBMs Bar has ...

11. Problem with any association and a composite-id    forum.hibernate.org

Newbie Joined: Thu Oct 23, 2003 10:55 am Posts: 11 Hello All, I have a problem with an association between a Class and an Abstract class with the one table per concrete class stategy identified with a composite-id. An exception occurs when Hibernate read the mapping files. Does anybody have a clue? Is there a problem with the mapping? Thx in ...

12. Association table mapping problem with composite-element    forum.hibernate.org

Hi all, I want to map the J2EE security model, which say that a User may have a collection of Roles. But I have an exception thrown, telling me that the Role object is not an instance of declaring class. Maybe my error is evident, but I cannot see anything wrong. My database design use 3 tables (user, role, and userrole) ...

13. Not inserting association column based on composite keys    forum.hibernate.org

Author Message fgkalways Post subject: Not inserting association column based on composite keys Posted: Tue Jan 17, 2006 6:08 am Newbie Joined: Sun Jul 31, 2005 11:12 pm Posts: 8 I'm trying to add a sheet with an association to a 'guido'. I call setGuido(guido) on the sheet object then I try to save the sheet, the columns of ...

14. Tricky composite-id association - is this possible??    forum.hibernate.org

Hi Folks, I'm trying to map a legacy table structure that uses a generic lookup table for lookup values. Unfortunately the way it was implemented is not optimal and is making the mapping difficult. Here are the lookup table columns: - lookupid (auto-generated PK) - type (varchar type of the lookup item. ex: 'state', 'personstatus', etc) - lookupvalue (the value of ...

15. composite key and single key mapping association    forum.hibernate.org

Hi, If i have table say, "TABLEA" which has a primary key on one column, lets say on "COLM1" and has another table "TABLEB", which has a composite key of two columns (COLM1 and COLM2). If i want to have an association with these tables, what should i put in the mapping xml file? CLASSA represents TABLEA CLASSB represents TABLEB. CLASSA ...

16. composite-id in one-to-one association    forum.hibernate.org

Hi all, I have 3 tables :Subject,SubjectPlan and Document every Subject has its own plan, and in plan table, each plan is connected with document table,which contains the plan document. Subject has composite id : A+ B--one-to-one--> SubjectPlan I have looked in hibernate document, around google, but cant help. Do you guys have any experience of how to specify it in ...





17. composite-id problem with many to many associations    forum.hibernate.org

Author Message BenDave Post subject: composite-id problem with many to many associations Posted: Thu May 22, 2008 3:32 pm Newbie Joined: Wed Apr 30, 2008 1:49 pm Posts: 7 Hi, I am trying to perform a simple example for a many to many association. My two classes are Zone and ZoneSet and the class representing the association is ZoneToZoneSet. ...

18. Composite Identifier with associations throws NullPointers    forum.hibernate.org

I have a seemingly insurmountable issue with a compisite identifier. I think it might be a legitimate bug, and I'd like some opinions and ideas. I have a legacy database that I must map objects against. I cannot modify the database structure. In that database, Enterprises are associated to Addresses with a join table. This join table, ENT_ADDR, has 3 columns: ...

19. Association of two tables using composite key    forum.hibernate.org

Hi, I need the solution for the following. Thank you in advance. Problem Description ------------------- I have two tables User and a Group In User table the composite key is (cid, groupid, userid) In Group table the composite key is (cid, groupid) The (cid, groupid) part of Users' composite key refers the key in Group table The query to be generated ...

21. Composite Key w/ association and generated value?    forum.hibernate.org

Hi, First of all, Happy New Year ! Then, I have a problem :-) And it is just the beginning of the year.. My problem is Hibernate. I try to do a mapping on a view and i'm passing by a composite-id for the ID but i get an error. I dunno if it is a problem in my view table ...

22. many-to-many using an association class and composite ids    forum.hibernate.org

Newbie Joined: Thu Jan 08, 2009 3:48 pm Posts: 3 Location: San Francisco I'm having trouble using Hibernate 3.3.1 to implement a many-to-many association using an association class and composite keys, so I'm putting this out to the community in order to gain feedback on what I'm doing wrong in terms of design and/or Hibernate usage. Background to the problem: I'm ...