amend add page

hi. in addition to adding items to a db i also need the ability to retrive items from the db. i have tried the following code:
[codebox]//$id = $_POST['editid1'];

$_SESSION['retrive'] = $_POST['editid1'];

//echo $_SESSION['id'];

global $conn;

$query = "UPDATE items SET status = '9' WHERE id_frm = ".$_SESSION['id'];

db_exec($query,$conn);

return true;[/codebox]
which throws an sql error because the add page is trying to insert the record. can the add page be modified to achieve this function? many thanks