@After
  public void tearDown() throws Exception {
    try {
      if (d != null) {
        dropTables();
        d.close();
        d.destroy();
        d = null;
      }
      TestTxnDbUtil.cleanDb(hiveConf);
    } finally {
      FileUtils.deleteDirectory(new File(TEST_DATA_DIR));
    }
  }
this is to test differety types of Acid tables
itests/hive-unit/src/test/java/org/apache/hadoop/hive/ql/TestAcidOnTez.java