@Test
  public void testConcurrent2InsertOverwritesDiffPartitions() throws Exception {
    testConcurrent2InsertOverwrites(false);
  }
run a merge statement using un-partitioned target table and a concurrent op on the target
Check that proper locks are acquired and Write conflict detection works and the state
of internal table.
@param causeConflict true to make 2 operations such that they update the same entity
ql/src/test/org/apache/hadoop/hive/ql/lockmgr/TestDbTxnManager2.java