About Entity

forum_thread

Pessimistic lock

Dear Sir or Madam, In the past we used the default Options in the JDO 1.0. See below for reference: javax.jdo.option.Optimistic=false javax.jdo.option.NontransactionalRead=true javax.jdo.option.NontransactionalWrite=false javax.jdo.option.RetainValues=true javax.jdo.option.RestoreValues=false Now we use the following options in DB2: ... "com.objectdb.o._JdoUserException: Attempt to lock an entity object by retrieval when no transaction is activ." This is only in DB2. ...

 
forum_thread

@OrderColumn issue

Hi All, For some reason I'm not able to make the @OrderColumn annotation work. The test case is attached to the thread. Kind regards ... ignored by ObjectDB. This is because ObjectDB does not map entity objects to underlying tables and therefore does not handle columns. ...

 
forum_thread

Field level privileges

Hello , we are currently making new instant messenger but we were planing to use some security addons and privileges on access some of the fields on java side.   Can we give privileges to users , for example some users can only read some fields and some just can write java fields. Some users only allowed insert ability. Anonymous access only accesses some of the fields. ... users anyway. It is easy to manage application users as entity objects and use only minimal number of ObjectDB users (one or a few) to ...

 
tutorial

Getting Started with JPA

Getting started tutorial for step by step quick start with using Java Persistence API (JPA).... uses JPA to store and retrieve simple  Point entity objects, where each  Point has two persistent fields -  x ...

 
forum_thread

Detaching objects after JOIN FETCH

Hi, I have a question about detaching objects after issuing query with JOIN FETCH. Let's say I have two classes: public class A { @ManyToOne B bClass } public class B { @OneToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL) List<A> aClasses; } Now, I want to fetch all B classes with all A classes skipping lazy loading: ... b JOIN FETCH b . aClasses After closing entity manager, B classes became detached but without A classes and because EM ...

 
api-jpa

executeUpdate()

Execute an update or delete statement.(Method of javax.persistence.Query)

 
api-jpa

javax.persistence.PrePersist

Is used to specify callback methods for the corresponding lifecycle event.(Annotation of JPA)

 
api-jpa

javax.persistence.PostPersist

Is used to specify callback methods for the corresponding lifecycle event.(Annotation of JPA)

 
api-jpa

PersistenceUnit.unitName

(Optional) The name of the persistence unit as defined in the persistence.xml file.(Annotation Element of javax.persistence.PersistenceUnit)

 
api-jpa

javax.persistence.metamodel.Bindable

Instances of the type Bindable represent object or attribute types that can be bound into a Path.(Interface of JPA)