object « Join « JPA Q&A

  1. JPA Q&A
  2. Join
  3. object




1. Hibernate - join un related objects    stackoverflow.com

I have a requirement, wherein I have to join two unrelated objects using Hibernate HQL. Here is the sample POJO class 

class Product{
int product_id;        
String name;
String ...

2. Hibernate - Object Graph using outer join    coderanch.com

Hi, I want to create Object Graph from three (or more) related tables by querying it with criteria. I have learnt that using left join fetch we can do it in single query but it seems there are certain limitations. I have following mappings: Question.hbm.xml

3. Hibernate join into single object    coderanch.com

I would like to do a select that joins two tables by id (j.id = m.jobId) and get a single value (j.name) that will be single object. When I make a join call, I get an array of objects. I need to pass a single type of object to a DisplayTag page. What is the best way to do this? Jim ...

4. how can i get one object from an inner join?    forum.hibernate.org

i use a HQL like this: "from Post as post inner join fetch post.thread , post.thread.forum" in my opion , it will return an object instance of Post , am i right? but when i do this, java.lang.ClassCastException is thrown Code: Collection result = testquery.list(); logger.debug("get test post list ...

5. how to use criteria join many object?    forum.hibernate.org

I find Criteria + Example is a good way to implement most query. But I happen a query and I do not know how to use Example to query. Class A join B, C, D with many-to-one or one-to-one association. A query codition include sample data of Class A, B, C, D. I try this way to query Code: ...

6. Hibernate Joins and objects    forum.hibernate.org

How does Hibernate process a join result if the result has not been mapped to a defined class? For instance if my user table/mapping includes columns a b c, and my books table/mapping includes columns a d e, my join may look like the following: select user.a, b, d, e from user, books where user.a = "xyz" and user.a = books.a; ...

7. Pulling back objects that join two tables calls upadate..?    forum.hibernate.org

I have what seems like a very odd situation. I have an Image Object (id and filename) which has a ref to a DataObject (the image byte[] data). when pulling back the images the following sql is ran select image0_.id as id, image0_.filename as filename9_ from Image image0_ followed by a series of... select data0_.id as id0_, data0_.data as data5_0_ from ...

8. multiple inner joins with the same Object in HQL    forum.hibernate.org

9. How to get only one object from Criteria with some joins?    forum.hibernate.org

Hello. I've complex Criteria with several joins (createAlias for many-to-one and other relations). And after criteria.list() I got a list of Object[], where every class from join is situated in separate array item. But I really need objects for only one base class - class for whom I had created my Criteria. For example, sessionFactory.getCurrentSession().createCriteria( Account.class, "account" ); So I need ...