collection « Fetch « JPA Q&A





1. Hibernate collection fetching optimally    stackoverflow.com

I have the following structure Store
Rebate
RebateMetadata
RebateCommission So, the relation is like this - Store ...

3. (newbee) How to NOT fetch a collection    forum.hibernate.org

Hi everybody. I'm having a problem with Hibernate, I've googled a lot with no success. I have a class "Lots" which is part of a 1-to-many relationshio with a class "Documents", I mean one lot has N documents (a collection of documents). The problem is, sometimes I don't want hibernate fetch the documents, I just want query the Lots data. But ...

4. [solved] join fetch on empty collections    forum.hibernate.org

5. Fetching parts of a collection    forum.hibernate.org

Hi I have a Classrom object which holds collection of Student objects. I want to build a query that gives me all the classrooms with specific students. I tried this: from Classroom c left outer join c.students as student where student.birthYear > 1981; This is not good, because it returns a Classrom, and all of the Students, if one student's birth ...

6. Fetching sub-collections    forum.hibernate.org

Author Message Manopower Post subject: Fetching sub-collections Posted: Fri Nov 18, 2011 6:51 am Newbie Joined: Fri Nov 18, 2011 6:38 am Posts: 1 Hello, i'd like to get from my HQL request 50 Automates and for each, fetch their collection of Anomalie, Indispo and Connexion. (Spring Batch Reader) VueAutomateED mapping : Code: ...

7. Can't fetch collection    forum.hibernate.org

Hi! I am having difficulties with the fetching of a collection. Although the data is in the database, the getter method doesn't retrieve it. It comes down to this example: child.hbm.xml: Code: ...

8. failing to retrieve a collection    forum.hibernate.org

i'm new with hibernate (and spring), i am having troubles trying to retrieve a collection (defined as lazy). Here is the relevant code: Father.hbm.xml Code:

9. deeper fetch collections    forum.hibernate.org

Hello, I have a question about fetch sql collection. For my domain model, I have a Event, which has a Set of Market; Market has a Set of order. Can I get all these Sets by fetch sql? We know that using "from Event event left join fetch event.markets where eventId=?" can give us the Event with initialized Set of markets. ...





10. HQL: How to fetch a Collection in a tuple?    forum.hibernate.org

Hi, I want to fetch 2 classes that have no directly mapped relation. I want to get them as Object[], where object[0] is the first class, and object[1] is a collection of all elements of the second class. Imagine that I have a Poll that has several Questions. Each Visitor can give an Answer to every Question in a Poll. Now ...

11. Fetch Join and uninitialized collections    forum.hibernate.org

Hibernate version: 3.2GA Mapping documents: What I have is a parent with a set of child objects beneath it. Each of these child objects has other objects in an object graph. What I'd like to do is for each parent object, I'd like to get some subset of the full collection of child objects using a fetch join (to do this ...

12. Fetch collection of collections    forum.hibernate.org

Author Message jlage Post subject: Fetch collection of collections Posted: Tue Feb 27, 2007 12:44 pm Newbie Joined: Tue Feb 27, 2007 12:31 pm Posts: 8 Location: nyc it seems i can't do a fetch on a one-to-many relation of a setup of objects that were fetched using a one to many from the parent. why? if you look ...

13. hibernate collection lazy fetching, a detailed question    forum.hibernate.org

Newbie Joined: Fri Sep 14, 2007 12:41 pm Posts: 1 Hi, I should like have an help for this problem about hibernate lazy collection mapping. My question is conceptual more than practical and is intended to understand the real way hibernate works and perhaps is not trivial. I think. I read many times the hibernate documentation but was not able to ...

14. How to fetch collection based on conditions    forum.hibernate.org

Consider this example There is a Class called Department ( Department has a Set of Sections ) Department has Sections ( Sections has Set of Students ) And Sections has Students. ( Students has properties has name) Now I want to retrieve a Department where student has a name eg section.student.name = "Sam" when I retrieve the Department , it should ...

15. fetching many-to-many collection    forum.hibernate.org

Hi, I've been using Hibernate for a while but every now and then there is something I just don't understand - like this: This is the mapped class (importang part separated): Code: ...

16. fetching data through collection    forum.hibernate.org

hi I am stuck with a problem on retrieving datas through Collection and am unable to solve it . Configuration conf=new Configuration().addResource("Mapping/person.hbm.xml"); SessionFactory sf=conf.buildSessionFactory(); Session sess=sf.openSession(); Transaction tr=sess.beginTransaction(); Person p1=(Person)sess.get(Person.class,new Long(4)); Set s=p1.getAddress()//this method is supposed to return collection of address. tr.commit(); sess.flush(); sess.close(); Person.hbm.xml ...





17. fetching data through collection    forum.hibernate.org

hi I am stuck with a problem on retrieving datas through Collection and am unable to solve it . Configuration conf=new Configuration().addResource("Mapping/person.hbm.xml"); SessionFactory sf=conf.buildSessionFactory(); Session sess=sf.openSession(); Transaction tr=sess.beginTransaction(); Person p1=(Person)sess.get(Person.class,new Long(4)); Set s=p1.getAddress()//this method is supposed to return collection of address. tr.commit(); sess.flush(); sess.close(); Person.hbm.xml ...

18. Mutliple collections fetching creates cartesian product?    forum.hibernate.org

Say I want to fetch a person with all his sons and daughters from the database: "select p from Person p left join fetch p.sons left join fetch p.daughters where p.id = 5" Person has the properties Set sons and Set daughters. If person with id 5 has 7 sons and 3 daughters, the select generates resultset of 21 rows, which ...

20. 1 fetch="join" on a collection per class?    forum.hibernate.org

21. firstResult/maxResults specified with collection fetch; appl    forum.hibernate.org

The function works but i get the following in the stdout.log: firstResult/maxResults specified with collection fetch; applying in memory! A SaleItem has media and media has a list of pictures (max 3 atm) How can i get 50 SaleItems without getting the warning? And if there is no other solution...will the pictures be cached if i use eg a ehcache ? ...

22. How to prevent large collection fetching?    forum.hibernate.org

Newbie Joined: Mon Jan 16, 2006 8:41 am Posts: 6 Hello, I am handling two type of objects. The first is a Visit, which keeps track of a user visit to a web site, the second is the user itself. So we have: User.getVisits() ==> Collection of visits. As soon as the user logs in to the web page, i create ...

23. How to fetch collection?    forum.hibernate.org

Hi! I'm just new to Hibernate. I've a question with fetching collections. I'm solving the following problem: ex. I've table User and it is associated with tables Address, Email, Phone. I need to get information about all users (about 1.000.000) so I need to retrieve some fields from associated tables (ex. Address.Street Address.City, etc.) for each user. Now it takes too ...

24. Retrieve collections using a join    forum.hibernate.org

25. Manual fetching of collections    forum.hibernate.org

Hi pkleindl, I have played around a bit with the subselect fetching strategy and it would actually do what I want. What I need to check is whether it would work fine in our application where we typically have the following pattern: 1. load some root objects 2. load a set of collection properties of the root objects 3. edit the ...

26. Help with lazy fetching - collections not initialized    forum.hibernate.org

Newbie Joined: Thu Jun 04, 2009 10:02 am Posts: 6 Hi all, I guess you get a lot of questions about this, and I can understand this now, after 8 hours on work not getting any further :) I have searched and googled forever, read articles, documentation etc. but I am still not sure, I get the core idea of this, ...