PHP - 下载给定视频网址的对话框

I am pretty new in php .so hopefully this all make sense . I am using below script to extract url from database.I want down-loader will popup in browser while reading the url from database....

 $q="  Select url from videos where id = '".$_REQUEST['id']."'   ";
     $result=mysql_query($q);
           while( $rows =mysql_fetch_assoc($result) )
            {
        $url=$rows['url '];
    //here i want code to send this url to down-loader of browser..
    //and browser should popup the down-loader
        $myarray1=array("url "=>$url );
             }

I have searched codes on google but i don't understand how to use for this scenario...

First of all, you need to fix the SQL Injection problem. Use MySQLi instead of MySQL

Here's a code:

$request_id = isset($_REQUEST['id']) ? $_REQUEST['id'] : '';
if(!empty($request_id)){
    $mysqli = new mysqli("localhost", "user", "password", "database_name");
    $request_id = $mysqli->real_escape_string($request_id);
    $query = "SELECT url FROM videos WHERE id='" . $request_id . "'";
    $query_result = $mysqli->query($query);
    if(!empty($query_result)){
        if($query_result->num_rows > 0){
            $my_result_array = array();
            while($row = $query_result->fetch_assoc()){
                $my_result_array[] = $row['url'];
            }
        }
    }
    mysqli_close($mysqli);
}

Concerning the download problem, you need to redirect the user to a PHP page with a specific header

<?php
$file_name = "";
header("Content-Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
header("Content-Disposition: attachment;filename=\"" . $file_name . "\"");
header("Cache-Control: max-age=0");
?>

You need to add the $file_name and the specific Content-Type. Here's a list of Content-Types: http://davidwalsh.name/php-header-mime

In order to redirect a user to the download page, you can use the PHP header() function.