<result>
  {
  let $current-date := xs:date('1999-01-31') return
    for $i in doc("items.xml")//item_tuple
    where $i/start_date <= $current-date
      and $i/end_date >= $current-date 
      and contains($i/description, "Bicycle")
    order by $i/itemno
    return
        <item_tuple>
            { $i/itemno }
            { $i/description }
        </item_tuple>
  }
</result>