如何根据需要正确格式化sql json

Question

Basically,I want to fetch data from mysql and format it into json like this:

[
  [
    "title" => "first",
    "uploader" => "root"

  ],
  [
    "title" => "first",
    "uploader" => "root"
  ],
  [
    "title" => "first",
    "uploader" => "root"
  ],
  [
    "title" => "first",
    "uploader" => "root"
  ],
  [
    "title" => "first",
    "uploader" => "root"
  ],
  [
    "title" => "first",
    "uploader" => "root"
  ],
   [
    "title" => "first",
    "uploader" => "root"
  ],
  [
    "title" => "first",
    "uploader" => "root"
  ],
  [
    "title" => "first",
    "uploader" => "root"
  ],
   [
    "title" => "first",
    "uploader" => "root"
  ],

]

I used this code:

<?php
require 'config.php';

            $query = $_GET['q'];
            if ($query==null) {
                exit('No query');
            }

$sql = "SELECT title,uploader FROM `uploads_public` WHERE Title =:query ";

        if($stmt = $pdo->prepare($sql)){
            // Bind variables to the prepared statement as parameters
            $stmt->bindParam(":query", $query, PDO::PARAM_STR);




            // Attempt to execute the prepared statement
            if($stmt->execute()){
               echo "Your search $query has the following results(normal json):<br>";
               $results = $stmt->fetchAll(PDO::FETCH_ASSOC);
               $json = json_encode($results);
               echo($json).'<br>';

               echo "While it has the following results when replaced<br>";
               echo  str_replace('}',']',str_replace(':','=>',str_replace('{', '[', "$json")));





         } else{
                echo "Something went wrong. Please try again later. <br>"; print_r($stmt->errorInfo());
            }
                    // Close statement
        unset($stmt);
        unset($pdo);
        }





   else{
    echo "No input";
} 

But rather than what I wanted(mentioned above),i got this:

[["title"=>"first","uploader"=>"root"],["title"=>"first","uploader"=>"root"],["title"=>"first","uploader"=>"root"],["title"=>"first","uploader"=>"root"],["title"=>"first","uploader"=>"root"],["title"=>"first","uploader"=>"root"],["title"=>"first","uploader"=>"root"],["title"=>"first","uploader"=>"root"],["title"=>"first","uploader"=>"root"]]

It looks ok,but the major problem is that I don't want all the results compressed together ,I want it exactly the way mentioned..with line breaks(new lines) after every ..[,", and so on

Thanks