<?php
$sql="select * from doc_in , department , memberuser where
id_number='$id_number' and
doc_in.id_department=department.id_department and
memberuser.id_department=department.id_department
and status_in='dam'
ORDER BY number_in DESC" ;
$ans= mysql_query($sql);
$num = mysql_num_rows($ans);
echo $num
?>