Actually you need not to create temporary file you can load data directly from server side script
grid.loadXML(“some.php”) //or some.jsp, some.aspx - any server side script can be used
in some.php
<?php
header("Content-type:text/xml");
echo "<?xml version='1.0' ?>";
echo “”;
//connect to DB
//fetch necessary data
//output it as XML
echo "<row…