reference to check items using unlang

Hi All, How can I reference to check items using unlang? When I use perl script , simply reference it by $RAD_CHECK. For example I want to check if there is a check item in sql user profile , then do some actions using unlang and if not then ignore it. By the way I know that I can do that by querying sql in unlang but I wondering if there is a better way for doing that. Could you please help me? Regards, Nasser