diff --git a/database/db_types.anubis b/database/db_types.anubis
index b1874b4..e2722c1 100644
--- a/database/db_types.anubis
+++ b/database/db_types.anubis
@@ -67,6 +67,18 @@ public define Int
     none        then (Int)-1,
     db_id(_idx) then _idx
   }.
+
+public define DB_id
+  to_DB_id
+  (
+    Int value
+  )=
+  if value < 0 then 
+    none 
+  else 
+    db_id(value)
+.
+  
   
 public define String
   to_String
--
libgit2 0.21.4