diff --git a/api/core/app/apps/workflow_app_runner.py b/api/core/app/apps/workflow_app_runner.py
index 2817313e5d..c1372e6f4d 100644
--- a/api/core/app/apps/workflow_app_runner.py
+++ b/api/core/app/apps/workflow_app_runner.py
@@ -735,7 +735,7 @@ class WorkflowBasedAppRunner(AppRunner):
                 invoke_from=self.queue_manager._invoke_from,
                 enclosing_node_id=event.in_loop_id or event.in_iteration_id or None,
             )
-            draft_var_saver.save(process_data=process_data, output=outputs)
+            draft_var_saver.save(process_data=process_data, outputs=outputs)
 
 
 def _remove_first_element_from_variable_string(key: str) -> str:
diff --git a/api/services/workflow_draft_variable_service.py b/api/services/workflow_draft_variable_service.py
index 870523877e..5412d4b923 100644
--- a/api/services/workflow_draft_variable_service.py
+++ b/api/services/workflow_draft_variable_service.py
@@ -550,10 +550,14 @@ class DraftVariableSaver:
             )
         return draft_vars
 
-    def save(self, output: Mapping[str, Any] | None, process_data: Mapping[str, Any] | None = None):
+    def save(
+        self,
+        process_data: Mapping[str, Any] | None = None,
+        outputs: Mapping[str, Any] | None = None,
+    ):
         draft_vars: list[WorkflowDraftVariable] = []
-        if output is None:
-            output = {}
+        if outputs is None:
+            outputs = {}
         if process_data is None:
             process_data = {}
         if not self._should_save_output_variables_for_draft():
@@ -561,13 +565,13 @@ class DraftVariableSaver:
         if self._node_type == NodeType.VARIABLE_ASSIGNER:
             draft_vars = self._build_from_variable_assigner_mapping(process_data=process_data)
         elif self._node_type == NodeType.START:
-            draft_vars = self._build_variables_from_start_mapping(output)
+            draft_vars = self._build_variables_from_start_mapping(outputs)
         elif self._node_type == NodeType.LOOP:
             # Do not save output variables for loop node.
             # (since the loop variables are inaccessible outside the loop node.)
             return
         else:
-            draft_vars = self._build_variables_from_mapping(output)
+            draft_vars = self._build_variables_from_mapping(outputs)
         _batch_upsert_draft_varaible(self._session, draft_vars)
 
     @staticmethod
diff --git a/api/services/workflow_service.py b/api/services/workflow_service.py
index 2300246336..0d3aa85c30 100644
--- a/api/services/workflow_service.py
+++ b/api/services/workflow_service.py
@@ -395,15 +395,12 @@ class WorkflowService:
 
         # Convert node_execution to WorkflowNodeExecution after save
         workflow_node_execution = repository.to_db_model(node_execution)
-        process_data = workflow_node_execution.process_data_dict or {}
-        output = workflow_node_execution.outputs_dict or {}
 
         exec_metadata = workflow_node_execution.execution_metadata_dict or {}
 
         loop_id = exec_metadata.get(WorkflowNodeExecutionMetadataKey.LOOP_ID, None)
         iteration_id = exec_metadata.get(WorkflowNodeExecutionMetadataKey.ITERATION_ID, None)
 
-        # TODO(QuantumGhost): single step does not include loop_id or iteration_id in execution_metadata.
         with Session(bind=db.engine) as session, session.begin():
             draft_var_saver = DraftVariableSaver(
                 session=session,
@@ -413,7 +410,7 @@ class WorkflowService:
                 invoke_from=InvokeFrom.DEBUGGER,
                 enclosing_node_id=loop_id or iteration_id or None,
             )
-            draft_var_saver.save(process_data=process_data, output=output)
+            draft_var_saver.save(process_data=node_execution.process_data, outputs=node_execution.outputs)
             session.commit()
         return workflow_node_execution