Free Oracle 1Z0-898 Exam Dumps Questions & Answers

If a Persistence application locks entity x with a pessimistic lock, which statement is true?

• A.  The Persistentprovider will lock the database row(s) that correspond to all persistent fields of properties of an instance, including element collections.
• B.  A separate lock statement must be called for each subclass in entity hierarchy.
• C.  Only single table per class hierarchy mapping is supported with this lock type.
• D.  A Persistence provider will lock the entity relationships for which the locked entity contains the foreign key.

Persistence application locks entity x with a LockModeType. PESSIMISTIC_READ lock type, which statement is true?

• A.  This operation will force serialization among transactions attempting to read the entity data.
• B.  If the application later updates the entity, and the changes are flushed to the database, the lock will be converted to an exclusive lock.
• C.  LockModeType. PESSIMISTIC_READ is the synonym of the LockModeType.REA
• D.  This operation will result in a TransactionRolledbackException if the lock cannot be obtained.

Given the following code:
Public void create () {
try {
doA () {
} catch (PersistenceException e) {} try (doB) ();
} catch (PersistenceException e) {}
}
Calling method doA will cause an NonUniqueResultException to be thrown. Calling method doB will cause an EntityExistsException to be thrown.
What two options describe what will happen when the create method is called within an application ' uses container managed transactions? (Choose two)

• A.  The current transaction will continue after doB executes.
• B.  Method doB will never be called.
• C.  The current transaction will continue after doA executes.
• D.  The current transaction will be marked for rollback when doA is called.
• E.  The current transaction will be marked for rollback when doB is called.

Which cascade option can be specified in a mapping descriptor so that it applies to all relationships in a persistent e unit?

• A.  cascade remove
• B.  cascade all
• C.  cascade detach
• D.  cascade-persist

If an application uses an extended persistence context, which of the following is true?

• A.  The persistencecontext exists until all transactions invoked by the EntityManager complete.
• B.  The persistence context exists until the EntityManagerinstance is closed.
• C.  The persistence context exists until all transactions invoked by the EntityManagar complete and the EntityManager.clear () method is invoked.
• D.  The persistence context exists until the EntityManagerFactory instance is closed.