About field

api-jpa

javax.persistence.QueryTimeoutException

Thrown by the persistence provider when a query times out and only the statement is rolled back.(Exception of JPA)

 
manual

Running JPA Queries

Explains how to use JPA to run Java Persistence Query Language (JPQL) queries.... ; and the following query resets the area field in all the Country instances to zero: int count = em. ...

 
forum_thread

Memory consumption of empty Strings

After doing some memory related research in my program, I found a possible place for an enhancement of objectdb: My program has several entities which contain many String. Often some of these String are empty (""). To avoid unnecessary memory consumption, the String within the entities are initialized like: String firstName = ""; ... a new String, the user should be able to specify that this field should be loaded via Stirng.internal() (with all its advantages and ...

 
api-jpa

javax.persistence.EntityExistsException

Thrown by the persistence provider when EntityManager.persist(Object) is called and the entity already exists.(Exception of JPA)

 
api-jpa

javax.persistence.NonUniqueResultException

Thrown by the persistence provider when Query.getSingleResult() or TypedQuery.getSingleResult() is executed on a query and there is more than one result from the query.(Exception of JPA)

 
api-jpa

javax.persistence.NoResultException

Thrown by the persistence provider when Query.getSingleResult() or TypedQuery.getSingleResult()is executed on a query and there is no result to return.(Exception of JPA)

 
manual

[ODB1] Chapter 5 - JDO Connections

The PersistenShows how to use database connections and transactions in JDO. ceManagerFactory interface represents a factory of database connections. Its main role is to provide PersistenceManager instances. The PersistenceManager interface represents a database connection. Every operation on a database requires a PersistenceManager instance. The Transaction interface represents a transaction on a database. Every operation that modifies the content of the database requires an active transaction.[toc hidden:1] This chapter describes three essential interfaces for using JDO: 5.1  javax.jdo.PersistenceManagerFactory 5.2  javax.jdo.PersistenceManager 5.3  javax.jdo.Transaction The PersistenceManagerFactory ...

 
api-jpa

javax.persistence.RollbackException

Thrown by the persistence provider when EntityTransaction.commit() fails.(Exception of JPA)

 
forum_thread

Concerning coding style of the example in the posting instructions

(This forum item was spawned from discussions in a private helpdesk ticket.) I write with reference to the coding example in the posting instructions and many of your other examples posted in the forums. While I appreciate the recommended coding style as shown makes for convenient minimal examples and test cases,  I contest that it breaks the rules for JPA2 entities on at least 2 counts. Firstly, the posting instructions state:  #1 2012-03-14 00:28 (This forum item was spawned from discussions in a private helpdesk ticket.) I write with reference t ...

 
api-jpa

javax.persistence.TransactionRequiredException

Thrown by the persistence provider when a transaction is required but is not active.(Exception of JPA)