feast-dev
@@ -443,7 +443,16 @@ def get_table_column_names_and_types_from_data_source(
         return zip(table.column("name").to_pylist(), table.column("type").to_pylist())
 
 
-def _create_retrieval_metadata(feature_refs: List[str], entity_df: pd.DataFrame):
+def _create_retrieval_metadata(
+    feature_refs: List[str], entity_df: Optional[pd.DataFrame] = None
+):
+    if entity_df is None:
+        return RetrievalMetadata(
+            features=feature_refs,
+            keys=[],  # No entity keys when no entity_df provided
+            min_event_timestamp=None,
+            max_event_timestamp=None,
+        )
     entity_schema = _get_entity_schema(
         entity_df=entity_df,
     )

@@ -431,6 +431,9 @@ def get_historical_features(self, command: dict, key: Optional[str] = None):
             # Extract parameters from the internal flights dictionary
             entity_df_value = self.flights[key]
             entity_df = pa.Table.to_pandas(entity_df_value)
+            # Check if this is a mock/empty table (contains only 'key' column)
+            if len(entity_df.columns) == 1 and "key" in entity_df.columns:
+                entity_df = None
 
         feature_view_names = command["feature_view_names"]
         name_aliases = command["name_aliases"]