define function checkraised ($x) {
   if (exists(subsequence($x,3))) then (
     if (int($x[2]/text()) > int($x[1]/text())) then (
	$x[1]
     ) else (
      checkraised(subsequence($x,2))
     )
   )
   else ()
}
define function raised ($empno, $start, $end) {
  for $x in document('v-emps.xml')/employees/employee[empno=$empno]
    for $y in $x/salary[((date(@tstart) >= $start) and
                         (date(@tstart) <= $end)) or
                        ((date(@tend) >= $start) and
                         (date(@tend) <= $end)) or
                        ((date(@tstart) <= $start) and
                         (date(@tend) >= $end))]
    return $y
}
for $x in document('v-emps.xml')/employees/employee
let $start := $x/title[position()=1]/@tstart
let $end := $x/title[position()=2]/@tstart
let $empno := $x/empno/text()
where $x/title[last() > 1] and
empty (checkraised(raised($empno,date($start),date($end))))
return $x