About attribute

manual

[ODB1] Chapter 3 - Persistent Classes

Explains what a persistence capable class is and which types are supported by JDO. Persistent Classes are user defined classes whose instances can be stored in a database using JDO. Instances of these classes that represent objects in the database are called persistent objects or persistent instances . Objects that do not repre ...

 
forum_thread

Issue with Casting / Joins

Hi I can't seem to find my way out of this. Basically what I have is something like: ... . get ( "name" ) < -- fails with attribute "name" not found This somewhat makes sense because ...

 
forum_thread

Merge on detached entities

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 the entities. Can this works correctly? How are the rules of the merge process? Do the changed fields of the detached entity overwrite the fields in the database? Also changed fields which are set to null? #1 2017-09-19 09:54 Hello, it is possible to merge detached entities? There are some attached entities which load fro ...

 
api-jpa

join(map, jt)

Create a join to the specified Map-valued attribute using the given join type.(Method of javax.persistence.criteria.From)

 
forum_thread

Entity Management Config questions

Hi, the manual states the following regarding config of Entities: http://www.objectdb.com/java/jpa/setting/entities  : <cache ref="weak" level2="0mb" /> The <cache> element specifies settings of the two cache mechanisms for entities:... the two cache mechanisms for entities: The ref attribute specifies reference type for holding non dirty entities in the ...

 
api-jpa

CollectionTable.name

(Optional) The name of the collection table.(Annotation Element of javax.persistence.CollectionTable)

 
forum_thread

ObjectDB Explorer Exposes Username and Password

How can I prevent my database username and password from being exposed by ObjectDB Explorer? #1 2017-02-06 12:13 How can I prevent my embedded database's username and password from being exposed by ObjectDB Explorer? ...

 
api-jdo

Constants.PROPERTY_ATTRIBUTE_VALUE

The name of the persistence manager factory property element's "value" attribute.(Static Field of javax.jdo.Constants)

 
api-jpa

PluralAttribute.CollectionType.MAP

Map-valued attribute(Enum Constant of javax.persistence.metamodel.PluralAttribute.CollectionType)

 
api-jdo

Constants.PMF_ATTRIBUTE_CONNECTION_PASSWORD

The name of the persistence manager factory element's "connection-password" attribute.(Static Field of javax.jdo.Constants)