NoRowsModifiedSessionEvent Event Handler

As part of your general error handling strategy, you should implement a SessionEventListener for SessionEvent.NoRowsModifiedSessionEvent.

TopLink raises this event when an update or delete query is executed against the database, but no rows are updated, that is, a zero row count is returned.

If optimistic locking is not enabled and you query the database and violate your VPD security configuration, no exception is thrown: the query simply returns zero rows updated.

If optimistic locking is enabled and you query the database and violate your VPD security configuration, an OptimisticLockException is thrown even though the root cause of the failure was a security violation, not an optimistic locking issue.

Note: You must add this session event listener to the server session from which you acquire your isolated client session. You cannot add them to the isolated client session itself. For more information, see "Configuring Session Event Listeners"

Using Java

This event listener gives you an opportunity to determine whether the update failure was due to a security violation (in which case you should not retry the operation), or due to an optimistic lock issue (in which case a retry may be appropriate).

You can use the existing session event API, such as getQuery().getResult(), to get the affected object, if any.

After you implement the required SessionEventListener, add it to the parent server session, from which you acquire your isolated client session. For more information, see "Configuring Session Event Listeners".