About identity

manual

Auto Generated Values

Explains the different strategies for generating auto values (mainly for primary key fields) in JPA.... The Auto Strategy The Identity Strategy The Sequence Strategy The Table ... as explained in the previous section . The Identity Strategy The IDENTITY GenerationType.IDENTITY ...

 
api-jpa

GenerationType.IDENTITY

Indicates that the persistence provider must assign primary keys for the entity using a database identity column.(Enum Constant of javax.persistence.GenerationType)

 
issue

javax.jdo.JDONullIdentityException: The identity must not be null.

When stopping my JEE 6 Web Profile application in Glassfish 3.1.1, I sometimes get this exception, yielding in not merging athene.odb and athene.odb$. A bug in objectdb?    bjjl@ps2:~$ ls -l /var/db/athene/ total 122080 -rw-r--r-- 1 bjjl webservd   2621440 2012-05-24 16:40 athene.odb -rw-r--r-- 1 bjjl webservd 122265952 2012-05-24 16:40 athene.odb$ bjjl@ps2:~$   ... Caused by: javax.jdo.JDONullIdentityException: The identity must not be null.         at javax.jdo.identity.SingleFieldIdentity.assertKeyNotNull(SingleFieldIdentity.java:92) ...

 
api-jdo

javax.jdo.PersistenceManager

PersistenceManager is the primary interface for JDO-aware application components.(Interface of JDO)

 
api-jdo

javax.jdo.spi.PersistenceCapable

A class that can be managed by a binary-compatible JDO implementation must implement this interface.(Interface of JDO)

 
api-jdo

IdGeneratorStrategy.IDENTITY

(Enum Constant of javax.jdo.annotations.IdGeneratorStrategy)

 
api-jdo

javax.jdo.annotations.DatastoreIdentity

Annotation for the datastore identity of the class.(Annotation of JDO)

 
api-jdo

getObjectId(pc)

The ObjectId returned by this method represents the JDO identity of the instance.(Method of javax.jdo.PersistenceManager)

 
forum_thread

Is there a function of "drop table" or "delete from table"?

Besides the em.remove() one by one, is there a function of "drop table" or "delete from table"? TIA ... automatic global sequence . The name of an identity sequence (specific per entity class) is entityName + "$identity" . User defined generators ( sequence and table ) have ...

 
api-jdo

javax.jdo.JDOHelper

This class can be used by a JDO-aware application to call the JDO behavior of PersistenceCapable instances without declaring them to be PersistenceCapable.(Class of JDO)