mysql - How can I export a csv file of the sql data with php?

I currently have an app that displays about 4,000 items. I am pulling this from a mysql database. I am trying to create a button that will force a download of all of the items from the database into a csv file. How can I go about this?

csv.php

header('Content-Type: text/csv; charset=utf-8');
header('Content-Disposition: attachment; filename=data.csv');


$output = fopen('php://output', 'w');

fputcsv($output, array('Column 1', 'Column 2', 'Column 3'));

mysql_connect('localhost', 'root', 'root');
mysql_select_db('wp_xroads');
$rows = mysql_query('SELECT first_name,last_name,phone FROM bags');

while ($row = mysql_fetch_assoc($rows)) fputcsv($output, $row);
?>

html

  
    

        
          Export CSV 
        

    

thanks in advance.
-ken