private void createTimeSeriesTool(String storageGroup) throws SQLException {
    Set<String> resultList = new HashSet<>();
    try (Connection connection = EnvFactory.getEnv().getConnection();
        Statement statement = connection.createStatement();
        ResultSet resultSet = statement.executeQuery("show timeseries")) {
      while (resultSet.next()) {
        String str = resultSet.getString(ColumnHeaderConstant.TIMESERIES);
        resultList.add(str);
      }
    }
    Assert.assertFalse(resultList.contains(storageGroup));
    resultList.clear();
    try (Connection connection = EnvFactory.getEnv().getConnection();
        Statement statement = connection.createStatement();
        ResultSet resultSet = statement.executeQuery("SHOW DATABASES")) {
      while (resultSet.next()) {
        String res = resultSet.getString(ColumnHeaderConstant.DATABASE);
        resultList.add(res);
      }
    }
    Assert.assertTrue(resultList.contains(storageGroup));
  }
Test if creating a time series will cause the database with same name to disappear
integration-test/src/test/java/org/apache/iotdb/db/it/schema/IoTDBCreateTimeseriesIT.java