public void update(String i){
		
		Query query = new Query("UE_area");
	    query.addFilter("id_UE_area", FilterOperator.EQUAL, i);
	    PreparedQuery pq = datastore.prepare(query);
	    Entity UE_area = pq.asSingleEntity();
	    datastore.delete(UE_area.getKey());  
	}