fix: Empty knowledge base upload error (#1904)

apps/dataset/serializers/document_serializers.py

@@ -1046,7 +1046,7 @@ def batch_save(self, instance_list: List[Dict], with_valid=True):
             # 查询文档
             query_set = QuerySet(model=Document)
             if len(document_model_list) == 0:
-                return [],
+                return [], dataset_id
             query_set = query_set.filter(**{'id__in': [d.id for d in document_model_list]})
             return native_search(query_set, select_string=get_file_content(
                 os.path.join(PROJECT_DIR, "apps", "dataset", 'sql', 'list_document.sql')),