Create a JSON file using PHP + MySQL

json.php

<?php 
//http://stackoverflow.com/a/2467974

$query="SELECT * FROM tablename LIMIT 20"; 

$result=$mysqli->query($query)
	or die ($mysqli->error);

//store the entire response
$response = array();

//the array that will hold the titles and links
$posts = array();


while($row=$result->fetch_assoc()) //mysql_fetch_array($sql)
{ 
$title=$row['title']; 
$url=$row['url']; 

//each item from the rows go in their respective vars and into the posts array
$posts[] = array('title'=> $title, 'url'=> $url); 

} 

//the posts array goes into the response
$response['posts'] = $posts;

//creates the file
$fp = fopen('results.json', 'w');
fwrite($fp, json_encode($response));
fclose($fp);

/* Final Output

{"posts": [
  {
    "title":"output_from_table",
    "url":"output_from_table"
  },  
  ...
]}

*/
?> 

json_encode.php

<?php 
//http://stackoverflow.com/a/6282007

$return_arr = array();

$fetch = mysql_query("SELECT * FROM table"); 

while ($row = mysql_fetch_array($fetch, MYSQL_ASSOC)) {
    $row_array['id'] = $row['id'];
    $row_array['col1'] = $row['col1'];
    $row_array['col2'] = $row['col2'];

    array_push($return_arr,$row_array);
}

echo json_encode($return_arr);

/*returns a string like so:

[{"id":"1","col1":"col1_value","col2":"col2_value"},{"id":"2","col1":"col1_value","col2":"col2_value"}]
*/
?>

Nice scripts, tried it and works like a charm. But can you please guide how to parse this json data onto HTML tag with ID or class. I tried it but got undefined.

Thx