Issue regarding flow in php

Hi all , I have a php page . The php page is display when i have completed upload xml file to server. In the php page , there is a function name insertxmldataToTempTbl(), which insert xml data to MYSQL database as shown below after i have uploaded xml file to server , After insert xml data to MYSQL , i have function name compareTable()which do comparisation between the table A(XML data inserted) and table B(User data table)and store comparisation array data to the $_SESSION . However , sometimes when completed uploaded to xml file to server, the data is not display on the php page . I need to logout and login again then i can see the data on the same php page. PHP developer who have any ideas or suggestion , please email to me? Thanks.

         $data = $xml_util->getUnserializedData();
         insertxmldataToTempTbl($data);

         $compareTable();
         $comparearr = $_SESSION['LIST_SESSION'];
         $listchassis = $comparearr['listchassis'];

         $pagerOptions = array(
    'itemData'  => $listchassis,

'perPage' => 10,

    'delta' => 8,
    'useSessions' => true,
    'closeSession' => false,
    'mode' => 'Sliding'
    );

$pager = & Pager::factory($pagerOptions); $chassisdata = $pager->getPageData(); $links = $pager->getLinks(); while (list($name, $value) = each($chassisdata)) { blah blah blah -> List data in HTML table tag }