diff --git a/aiida/backends/sqlalchemy/models/workflow.py b/aiida/backends/sqlalchemy/models/workflow.py
index 1068623af0..7421bdcd5b 100644
--- a/aiida/backends/sqlalchemy/models/workflow.py
+++ b/aiida/backends/sqlalchemy/models/workflow.py
@@ -88,18 +88,14 @@ def set_script_md5(self, md5):
         self.script_md5 = md5
         self.save()
 
-    #    def add_data(self, dict, d_type):
-    #        for k in dict.keys():
-    #            p, create = self.data.get_or_create(name=k, data_type=d_type)
-    #            p.set_value(dict[k])
-
     def add_data(self, dict, d_type):
         for k in dict.keys():
             p, create = self._get_or_create_data(name=k, data_type=d_type)
             p.set_value(dict[k])
 
     def _get_or_create_data(self, name, data_type):
-        match_data = {name: _ for _ in self.data if _.name == name}
+        match_data = {name: _ for _ in self.data if _.name == name
+                      and _.data_type == data_type}
 
         if not match_data:  # create case
             dbdata = DbWorkflowData(parent_id=self.id, name=name, data_type=data_type)
@@ -250,7 +246,8 @@ def set_value(self, arg):
         try:
             if isinstance(arg, Node) or issubclass(arg.__class__, Node):
                 if arg.pk is None:
-                    raise ValueError("Cannot add an unstored node as an attribute of a Workflow!")
+                    raise ValueError("Cannot add an unstored node as an "
+                                     "attribute of a Workflow!")
                 sess = get_scoped_session()
                 self.aiida_obj = sess.merge(arg.dbnode, load=True)
                 self.value_type = wf_data_value_types.AIIDA
diff --git a/aiida/backends/tests/workflows.py b/aiida/backends/tests/workflows.py
index 9caa7d9d26..ce8b193893 100644
--- a/aiida/backends/tests/workflows.py
+++ b/aiida/backends/tests/workflows.py
@@ -241,6 +241,37 @@ def test_failing_calc_in_wf(self):
             if handler:
                 handler.setLevel(original_level)
 
+    def test_result_parameter_name_colision(self):
+        """
+        This test checks that the the workflow parameters and results do not
+        collide. This was a problem in SQLA (Issue #960) but a test for both
+        backends is added (for completeness).
+        """
+        # Creating a simple workflow & storing it
+        wf = WFTestEmpty()
+        wf.store()
+
+        # Set some parameters
+        params = {'band_calculation_set': 2,
+                  'codename': 'pw-5.2.0',
+                  'pseudo_family': 'SSSP_v0.7_eff_PBE'}
+        wf.set_params(params)
+
+        # Add some results that their names collide with the parameter names
+        wf.add_result('structure', 'test_string_1')
+        wf.add_result('codename', 'test_string_2')
+
+        # Check that we have the correct results
+        self.assertDictEqual(
+            {'structure': 'test_string_1', 'codename': 'test_string_2'},
+            wf.get_results(), "The workflow results are not the expected "
+                              "ones.")
+
+        # Check that we have the correct parameters
+        self.assertDictEqual(params, wf.get_parameters(),
+                             "The workflow parameters are not the expected "
+                             "ones.")
+
     def tearDown(self):
         """
         Cleaning the database after each test. Since I don't