--- lib/Arh/Model/UnitMaterial.pm	2007/11/29 00:34:22	2
+++ lib/Arh/Model/UnitMaterial.pm	2007/11/29 00:40:32	3
@@ -7,9 +7,11 @@
 use Arh::Record schema {
 
 	column unit =>
-		refers_to Arh::Model::Unit;
+		refers_to Arh::Model::Unit,
+		is required;
 	column material =>
-		refers_to Arh::Model::Material;
+		refers_to Arh::Model::Material,
+		is required;
 
 };