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Detached entity objects are objects in a special state in which they are not managed by any EntityManager but still represent objects in the database. Compared to managed entity objects, detached objects are limited in functionality: Many JPA methods do not accept detached objects (e.g. lock

: New, Managed, Removed and Detached . When an entity object is initially created its state is New ... deletion are provided in the Deleting Entities section. The last state, Detached , represents entity ... of an EntityManager become detached when the EntityManager is closed. Working with detached objects

(and so lazy loading would initially work), they become detached once the EntityManager under control ... are involved) to ensure the desired collections are resolved already before detachment , losing ... bean is released. 3. Use a FETCH JOIN as described here: Detach JPA objects with lazy initialized

Hello, it is possible to merge detached entities? There are some attached entities which load from the database. The transaction is finished and the entities become detached . In a new transaction the fields of the detached entities will be changed and a merge by em.merge(entity) will be saved

Hi, I have a question about detaching objects after issuing query with JOIN FETCH. Let's say I ... classes became detached but without A classes and because EM is closed, B.aClasses is always null. I thought, that after join fetch and CascadeType. DETACH list of A classes should be accessible from B

: objectdb.temp.no- detach NOT USED This problems only seems to occur in my large web application ... out what is happening and why. I am using pre- detach loading after em.find(id), because just relying on JPA-annotations ... these during the pre- detach loading should (and usually does) load everything needed to compute

JPA Method in jakarta.persistence.EntityManager void detach (   Object entity ... to become immediately detached . Unflushed changes made to the entity, if any, including deletion of the entity ... = DETACH . If the given entity instance is new or detached , that is, if it is not associated

out that all fields of retrieved objects are on their default value till i first call a getter or detach ... the transaction and the em. With 2.3.5_04 I get an empty detached user object back. Only the id is correct. Shouldn't the detach and field population happen implicitly during em.close()? mosi0815 Ralph Moser

Hello, the exception "Attempt to remove a detached entity object" have no information about the detached entity. It is very hard, especially if the involved entities uses cascading, to find the removed call for the detached entity.   It would be very helpful if you can add a few information

Hello, that's a strange error for me ... I have a detached object in my Java code and i just wanted to merge it ... Unfortunatly, i get this error : Failed to commit transaction: Attempt to remove a detached entity object (error 613)      at com.objectdb.jpa.EMImpl.commit

JPA Enum Constant in jakarta.persistence.CascadeType DETACH Cascade the plain operation Since: JPA 2.0

I have an entity that looks like this: class User {     @embedded private Profile profile;     ... } After running something like this:     User user = entityManager.createQuery("select......     entityManager. detach

that become detached (e.g. when the EntityManager is closed). Transparent activation is not supported for detached objects. Therefore, only content that has already been fetched from the database is available in objects that are detached . JPA 2 introduces methods for checking if a specified entity object

cannot be preserved for detached entity objects (explained in chapter 3 ) unless either the entity class

is not an instance of an entity class or if it is a detached entity. A TransactionRequiredException

with a persistent identity that is currently associated with a persistence context. A detached ... . An entity may be disassociated from the persistence context by calling detach , and a persistence context may be completely cleared, detaching all its entities, by calling () . The client may also make

A main limitation of detached objects (as explained on the Detached Entities manual page) is: Retrieval by navigation from detached objects is not supported, so only persistent fields that have been loaded before detachment should be used. As explained on the Object DB vs EclipseLink/TopLink

Hello, we've encountered an issue with ObjectDB. The attached code is a minimal example of the relevant work flow and fails at the assert in line 58: assertTrue(secondQueryResult.get(1).strValue != null); The entity is detached and data is not loaded lazily from the database. We've also found

performs this replacement operation also on detachment (rebuild and enhance your classes again to use this). So you can use now detached entity objects . Maybe you may even use detached entity objects ... Have you tried detaching entities before serializing them using GWT? objectdb.java.util.LinkedList is replaced

. Are you using enhanced classes? Are you using  "objectdb.temp.no- detach " ? Try to find the roots ... Yes, I use no- detach option. So how can I fix it? Remove no- detach ? But it has negative effects too. Vladiator Vlad Myachikov With "objectdb.temp.no- detach " enabled, clear() is silently ignored

is detached between the calls, check this issue and the no- detach solution. I have tried to clear ... . Actually clear detaches managed objects and could make things harder in this case. I have tried ... that transaction could be detached when I try to access the collection with the same EntityManager in the same

are detached and lazy relationships cannot be used, if not already loaded before when the  ... above. support Support OK, I'll try setting objectdb.temp.no- detach . Vladiator Vlad Myachikov Thank you! It works ... ? If it is related to the no- detach option then the same test case should work differently, depending

model) when I was using the experimental mode 'objectdb.temp.no- detach '. It was completely ... ), and only when I had 'objectdb.temp.no- detach ' true. When I had 'objectdb.temp.no- detach ... web app (too large to provide here) I however definitely have 'objectdb.temp.no- detach ' false and I

detached = pm.detachCopy(first); System.out.println(JDOHelper.isDetached( detached )); pmf.close(); } With this as the persistent class: @PersistenceCapable( detachable ="true") public class TestClass ... cannot tell the difference between a detached object and a transient object, so any detached object

the given object, whose state may be lazily fetched. The given object may be persistent or detached ... upon detachment , unless it was accessed by the application while the entity manager was open. Parameters: entity - a persistent or detached entity instance Return: a reference to the entity instance

-creating a detached copy 4-closing the connection 5-modifying the detached copy 6-re-opening the connection 7-saving the detached copy I get an "Attempt to reuse an existing primary key value" error. I ... merging detached objects is that JPA has a dedicated method,  merg e(obj), where JDO uses

;@PreUpdate).  The referencedObj is becoming null is after executing the following line: em. detach ... ). On detach some unloaded fields (inverse / mapped-by relationships) are nullified by ObjectDB to signal that they have not been loaded yet, as detached objects cannot handle automatic loading

;    root = em.find(Element.class, id); //now detached , since outside transaction   ... 'root', persist it, load 'root' again with find() outside a transaction as a detached entity ... it, load 'root' again with find() outside a transaction as a detached entity, then create an Example 'e

the state of the given new or detached entity instance into the current persistence context, resulting in ... , but a distinct Java object identity. If the given entity is detached , the returned entity has the same ... , and it is returned directly. Parameters: entity - a new, managed, or detached entity instance Return

;   -dh dhosek Don Hosek Fetching doesn't work by default for detached objects. Please read see this issue  and as a workaround you may try setting objectdb.temp.no- detach . support Support ... objects? -dh dhosek Don Hosek It would be better and more efficient, if possible, to arrange fetching of the relevant data before detachment . support Support

Gergely Jakab Build 2.6.3 adds an option to treat embedded objects on detachment (eventually ... .temp. detach -embeddable", "true"); Then embedded objects are expected to be disconnected when owner entity objects are detached (made transient). support Support The situation has been improved

. Guest 's toString is invoked in this tutorial on detached Guest instances, and in detached objects only fields that have been loaded before detachment (e.g. defined as eager rather than lazy, or

detaching User entity after query in #findUserById(Long id), but this shouldn't happen, at least in ... should be detached automatically (unless specified otherwise ), so probably that EntityManager ... objects of different entity managers as soon as possible. Accordingly, detaching the object before

;call, if the retrieved entity is dirty, call EntityManager# detach  on it and then call pm.getObjectById   ... the entity to become impossible to commit. Option 2 with EntityManager# detach sounds robust ... . detach that would do the same; PM.detachCopy doesn't work. I found that ObjectDB's implementation

cascade=ALL is equivalent to cascade={PERSIST, MERGE, REMOVE, REFRESH, DETACH }. See Also: ManyToOne ... ALL Cascade all operations Since: JPA 1.0 DETACH Cascade the plain operation Since: JPA 2.0 MERGE Cascade

Throws: EntityExistsException - if the given entity is detached (if the entity is detached , the {@code

an entity or is a detached entity TransactionRequiredException - if there is no transaction or if invoked

is not an entity or is a detached entity TransactionRequiredException - if invoked on a container

JPA Method in jakarta.persistence.EntityManager void clear () Clear the persistence context, causing all managed entities to become detached . Changes made to entities that have not already been flushed to the database will never be made persistent. Since: JPA 1.0

- if the instance is not an entity or is a detached entity TransactionRequiredException

- if the instance is not an entity or is a detached entity TransactionRequiredException

detached state, depending on whether a primary key is retrieved for the constructed object. Example

the instance state to be available upon detachment , unless it was accessed by the application

/retrieve EITHER: the transparent activation is failing AND/OR: entities are becoming detached . http://www.objectdb.com/java/jpa/persistence/ detach I can't find out how to test where an entity is detached ... this. webel Dr Darren Kelly My feeling (before running your application) is that indeed detachment

on an attempt to use a lazy collection that has not been loaded in a detached entity object. Build 2.3.1_03 ... empty - if it has not been loaded before detachment ). If an unexpected exception (e.g ... Support Thanks for that. Its interesting you mention the entity is detached though as that wasnt

is detached (e.g. when the EntityManager is closed), ObjectDB replaces lazy loaded collections that have not been loaded with null values. Detached objects cannot be refreshed. Does it happen ... are known as unloaded after detachment . This way you can easily tell the difference (after detachment

, CascadeType. DETACH }) private ModelElementImpl element; @OneToMany (fetch = FetchType.EAGER, cascade = {CascadeType.REFRESH, CascadeType. DETACH }) private HashMap mappingMap = new HashMap (1); (edited ... uid; @OneToOne (fetch = FetchType.EAGER, cascade = {CascadeType.REFRESH, CascadeType. DETACH }) private

on detachment to null (rather than empty collections ). Fixed a critical bug in handling a very large number ... EntityManager conflict checks in NO DETACH mode . Fixed a bug in online backup of databases larger ... another issue in implementing fake entity detachment (feature request #326 ). Fixed a bug in

. The NullPointerException indicates an unexpected state (the map seems to be detached , which is unexpected as the owner entity object is probably not detached ). It is unlikely that the exception is thrown ... type? What is the status of that object when it is refreshed (clean, dirty, detached , etc.)? Which maps

Added memory only database mode. Added an option to cascade detachment to embedded objects . Added ... memory management in multi flush transactions. Extended detachment of embedded objects ... handling large objects with long primary keys as query results ( issue #1717 ). Fixed detachment