diff --git a/lib/nntp/tiny/db.py b/lib/nntp/tiny/db.py
index 4ca423e..9777060 100644
--- a/lib/nntp/tiny/db.py
+++ b/lib/nntp/tiny/db.py
@@ -67,7 +67,7 @@ class Database():
         sql += ", ".join(['?' for c in table.columns if c != table.key])
         sql += ')'
 
-        fn = getattr(obj, '__values__')
+        fn = getattr(obj, '__values__', None)
 
         if fn is not None:
             values = fn()