form processing and viewing results

I have a page1.php which contains a post form and a page2.php which displays results. I have a seperate php script file that processes the form data and queries the database. What is the best, most efficient way of processing? Once the php script finishes querying the database, I would end up with, assuming the query returns a result,
while($result = mysql_fetch_assoc($query))
how do I get the data to the display page? Looking for examples I found one approach which is to have a go-between file which looks like this:
<?PHP
include_once(process.php);
process($_POST);
display_results;
?>
Can someone explain the display_results part? Is this a form of redirect? Any words of wisdom appreciated.

Why not display the results from the db query from the processing page? You don't need to have separate pages for processing form data and displaying the processed results

eg


<?php
$title = $_POST['txtTitle'];
$query = 'select title from books where title like "'.$title.'"';
$rs = mysql_query($query, $conn);
while($row=mysql_fetch_assoc($rs)) {
echo $row['title'].'<br />';
}
mysql_free_result($rs);
?>

Using include() simply inserts the code in the include file into your script as if it was written there originally.

include_once(process.php);

So if I'm connecting to a database in process.php, I have

$host = 'localhost';
$user = 'username';
$password = 'whatever';
Do I list these in a seperate file?