diff --git a/custom_menu_perms.install b/custom_menu_perms.install
index 6eda48e..03358e4 100644
--- a/custom_menu_perms.install
+++ b/custom_menu_perms.install
@@ -51,6 +51,7 @@ function custom_menu_perms_schema()
 				'description' => 'The menu path to which the permission will be used as the access arguments to be passed to user_access()',
 				'type' => 'varchar',
 				'length' => 255,
+				'not null' => TRUE,
 			),
 			'cmp_permission_key' => array
 			(