Database value convert to XML and json using php

Following code easy to use "Mysql /Any Database value convert to XML and json  using php" 

<?php



/* require the user_id as the parameter */
if(isset($_GET['user_id']) && intval($_GET['user_id'])) {

    /* soak in the passed variable or set our own */
    $number_of_posts = isset($_GET['num']) ? intval($_GET['num']) : 10; //10 is the default
    $format = strtolower($_GET['format']) == 'json' ? 'json' : 'xml'; //xml is the default
    $user_id = intval($_GET['user_id']); //no default

    /* connect to the database */
    $link = mysql_connect('localhost','root','') or die('Cannot connect to the DB');
    mysql_select_db('xmldb',$link) or die('Cannot select the DB');

    /* collect data the posts from the db */
    $query = "SELECT post_title, guid FROM pages";
    $result = mysql_query($query,$link) or die('Errant query:  '.$query);

    /* create one master array of the records */
    posts = array();


    //print_r($posts);
    if(mysql_num_rows($result)) {
        while($post = mysql_fetch_assoc($result)) {
            $posts[] = array('post'=>$post);
        }
    }

    /* output display as necessary format */
    if($format == 'json') {
        header('Content-type: application/json');
        echo json_encode(array('posts'=>$posts));
    }
    else {
        header('Content-type: text/xml');
        echo '<posts>';
        foreach($posts as $index => $post) {
            if(is_array($post)) {
                foreach($post as $key => $value) {
                    echo '<',$key,'>';
                    if(is_array($value)) {
                        foreach($value as $tag => $val) {
                            echo '<',$tag,'>',htmlentities($val),'</',$tag,'>';
                        }
                    }
                    echo '</',$key,'>';
                }
            }
        }
        echo '</posts>';
    }

    /* disconnect from the database */
    @mysql_close($link);

}
// XML Output given url run
//http://localhost/test/xmlcreate/xml.php?user_id=2&num=10


// Json Output given url run
//http://localhost/test/xmlcreate/xml.php?user_id=2&format=json
?>