Error with php and MySQL

Hello, i need help!!!

<?php 
    $query = mysql_query("SELECT 'id', 'name', 'url' FROM videos");
while($run = mysql_fetch_array($query)){
$video_id = $run['id'];
$video_name = $run['name'];
$video_url = $run['url'];
?>

Error:Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given in