If DataCache is enabled, and the default statement batching is active, there are cases that we fail to report OptimisticException.
Because of that, the cached objects were not get removed from the cache.
We have testcases running with different backend and returns different updateCount value from batchExecute when update failed:
1. DB2/NT, update count of 0 was returned
2. Oracle 10g, update count of -2 was returned.
The code in questioin is in BatchingPreparedStatementManagerImpl.checkUpdateCount() method.
We think the returned update count of 0 and -2 should report OptimisticException for UPDATE/DELETE SQL requests.
Current implemented code reports OptimisticException if update count of -3 is returned.
We don't know if any JDBC driver would return -3 for update/delete that did not qualify due to version value mismatch (in the case that the cache is out of sync with the database).