diff --git a/hub/persistence/repositories/simulation_results.py b/hub/persistence/repositories/simulation_results.py
index 08f655e8..2819049f 100644
--- a/hub/persistence/repositories/simulation_results.py
+++ b/hub/persistence/repositories/simulation_results.py
@@ -6,7 +6,6 @@ Project Coder Guille Gutierrez Guillermo.GutierrezMorote@concordia.ca
 """
 import datetime
 import logging
-from typing import Union, Dict
 
 from sqlalchemy import or_
 from sqlalchemy import select
@@ -109,7 +108,7 @@ class SimulationResults(Repository):
         raise NotImplementedError('Missing either city_id or city_object_id')
     except SQLAlchemyError as err:
       logging.error('Error while deleting application: %s', err)
-    return None
+      raise SQLAlchemyError(err)
 
   def _get_city(self, city_id) -> City:
     """
@@ -135,7 +134,7 @@ class SimulationResults(Repository):
       logging.error('Error while fetching city by city_id: %s', err)
       SQLAlchemyError(err)
 
-  def get_simulation_results_by_city_id_city_object_id_and_names(self, city_id, city_object_id, result_names=None):
+  def get_simulation_results_by_city_id_city_object_id_and_names(self, city_id, city_object_id, result_names=None) -> [Model]:
     """
     Fetch the simulation results based in the city_id or city_object_id with the given names or all
     :param city_id: the city id
@@ -151,11 +150,11 @@ class SimulationResults(Repository):
       results = [r[0] for r in result_set]
       if not result_names:
         return results
-      _ = []
+      filtered_results = []
       for result in results:
         if result.name in result_names:
-          _.append(result)
-      return _
+          filtered_results.append(result)
+      return filtered_results
     except SQLAlchemyError as err:
       logging.error('Error while fetching city by city_id: %s', err)
     return None