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10

Entity factory

Hi, is it possible to create Entities with a custom factory? I want to create Entity instances via dependency injection like: @Entiy public class User { private final UserService userService ... in a ThreadLocal and access it inside the new Entity to inject the dependencies.
Forum
10

Entity factory - best practices

initiate a db connection by creating entity manager factory from db on disk, get the entity manager, modify ... one every time. Out of curiosity, is my current method thread-safe? Can multiple entity managers exist
Forum
10

Entity has be persistended,but query not fetched?

I create a new entity T newT and persistend it,then I create a query "select t from T t" to fetch all T entities.But  then the newT is not contain in the query result. Why? code order: query ... ();         em.close();         emf.close();     }         @Entity     static final class User
Forum
10

Fetch a whole entity graph eager

Hello, I have two question at you. Are you provided JPA 2.1 annotation @NamedEntityGraph in next version ObjectDB 3.0? And do you know an easy possibility to get an entirely eager entity graph with all depended entities which we can use as a detached full accessible entity graph outside
Forum
10

How to check if an entity exists in a Database without loading it?

Hi, I am trying to speed up some code - where i check if an entity exists in order to make a decision. In Java - It looks like this (pk - is the primary key of the entity): MyClass find = em.find ... without loading the entity? Thanks   You can use a query: SELECT e.pk FROM MyClass e WHERE e.pk = :pk or SELECT COUNT(e) FROM MyClass e WHERE e.pk = :pk   EKK
Forum
10

Merge of entity classes with "mapped by" very slow

Hi, I have found a strange behavior when merging entities with "mapped by" set on @OneToMany ... - one with mapped by, second with adding entities list without "mapped by". The difference is huge event ... entity objects that are already managed should be very fast. Build 2.4.2_02 fixes it. If the problem
Forum
10

Merge with Parent/Child entities not possible

javax.persistence.Entity; import javax.persistence.EntityManager; import javax.persistence ... ; import org.junit.Before; import org.junit.Test; public class ObjectDbMergeTest { @Entity ... = id;   } } @Entity public static class ChildEntity {   @Id   @GeneratedValue   private
Forum
10

Populating entity id before transaction commit

transaction is committed so all returned entities are not populated with ID in this context. How can I force ODB to populate entity ID before transaction is committed? Or maybe there is another way to finding ID of entity before commit? You can use a SEQUENCE (or TABLE) value generation strategy
Forum
10

Removing an entity throws exception

to remove customer entity, when it's read by a query (it's attached), it throws this exception ... more   After this exception is the entity detached (why?). When I merge it, I can remove it without problems... The Customer class code: @Entity public class Customer implements Serializable { private
Manual
10

Database Management Settings

in the entity class or not. It can be disabled by setting the version-check attribute to false ... indexes are handled. When a new index is defined for an existing entity class that already has instances ... ObjectDB evaluation restrictions (of 10 entity classes and 1,000,000 entity objects per database) requires