@Test
  public void testFetchDeletedRowsUsingSortMergedDeleteEventRegistry() throws Exception {
    setupTestData();

    // To test the SortMergedDeleteEventRegistry, we need to explicitly set the
    // HIVE_TRANSACTIONAL_NUM_EVENTS_IN_MEMORY constant to a smaller value.
    int oldValue = conf.getInt(HiveConf.ConfVars.HIVE_TRANSACTIONAL_NUM_EVENTS_IN_MEMORY.varname, 1000000);
    try {
      conf.setInt(HiveConf.ConfVars.HIVE_TRANSACTIONAL_NUM_EVENTS_IN_MEMORY.varname, 1000);
      testFetchDeletedRows();
    }
    finally {
      // Restore the old value.
      conf.setInt(HiveConf.ConfVars.HIVE_TRANSACTIONAL_NUM_EVENTS_IN_MEMORY.varname, oldValue);
    }
  }
Tests that we can figure out min/max ROW__ID for each split and then use
that to only load delete events between min/max.
This test doesn't actually check what is read - that is done more E2E
unit tests.
@throws Exception
ql/src/test/org/apache/hadoop/hive/ql/io/orc/TestVectorizedOrcAcidRowBatchReader.java