diff --git a/lib/by_star.rb b/lib/by_star.rb
index e9997bd..3aff309 100644
--- a/lib/by_star.rb
+++ b/lib/by_star.rb
@@ -14,7 +14,7 @@ module ByStar
 
   def by_star_field(field=nil)
     @by_star_field ||= field
-    @by_star_field || "#{self.table_name}.created_at"
+    @by_star_field || "created_at"
   end
 
   include ByDirection