xmlreader attribute info

I am trying to read a large XML file and add it to a database.
Here is a very small example of the XML:

<?xml version="1.0" encoding="UTF-8"?>
<shows>
   <show id="33041">
       <title>The Sound of Music</title>
       <category>Musicals</category>
       <price currency="GBP">
           <min_price>12</min_price>
           <max_price>42</max_price>
       </price>
   </show>
</shows>

PHP:

The problem is that I do not know how to refer to the id value in <show id="33041">

Here is a snippet of code I am using:

    $xml = new XMLReader();
    $xml->open(Test.xml);
    while ($xml->read()) {
	        switch ($xml->name) {
			case "event":
            $xml->read();
            $conf["event"] = $xml->value;
            $xml->read();
            break;
			}
	}

PHP:

So how on earth do I get the id bit????

Thanks for any help.

 

$arr = array();
$xml = simplexml_load_file('Test.xml');
foreach($xml->show as $show) {
  $show_attributes = $show->attributes();
  $arr[] = $show_attributes['id'];
}
print_r($arr);

Code (markup):

$arr is an array populated with the id's of each <show> within <shows>

 

Thanks very much. That helps for small files but some of the XML I have are 500mb!
Thanks your code will help me.