Oracle 1Z0-898 Online Practice Questions and Exam Preparation

Oracle 1Z0-898 Online Questions & Answers

• Question 61:

  

  Which code fragment correctly defines the detail field that PersonDetail instance in removed if the person instance that references it is removed?

  A. @OneToOne (optional = false) personDetail detail;
  B. @OneToOne (optional = false) @mapsId PersonDetail Detail;
  C. @ OneToOne (orphanremoval = true) PersonDetail Detail;
  D. @ OneToOne (cascade = ORPHAN _ DELETE) @mapsId PersonDetail detail;
  C. @ OneToOne (orphanremoval = true) PersonDetail Detail;

• Question 62:

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

  A. Persistence provider can defer obtaining the lock until the next synchronization of an entity to the database.
  B. A Persistenceprovider will obtain the lock when the entity is refreshed from the database.
  C. A Persistence provider is not required to support the LockModeType. PESSIMISTIC_WRITE locking type.
  D. If a lock cannot be obtained, the Persistence provider must throw an exception.
  D. If a lock cannot be obtained, the Persistence provider must throw an exception.

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  Reference:http://www.eclipse.org/eclipselink/api/2.0/javax/persistence/LockModeType.html

  When the lock cannot be obtained, and the database locking failure results in transaction-level rollback, the provider must throw the PessimisticLockException and ensure that the JTA transaction or EntityTransaction has been marked for rollback.

• Question 63:

  A developer wants to write a type-safe Criteria API query. Which two of the following statements true about Criteria query roots? (Choose two)

  A. The query MUST define a query root.
  B. The query MUST define a query root only if it navigates to related entities.
  C. The query MUST NOT define multiple query roots.
  D. The query may define multiple query roots.
  B. The query MUST define a query root only if it navigates to related entities.
  C. The query MUST NOT define multiple query roots.

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  Reference:http://docs.jboss.org/hibernate/orm/4.0/hem/en-US/html/querycriteria.html

  http://stackoverflow.com/questions/3424696/jpa-criteria-api-how-to-add-join-clause-as-general- sentence-as-possible