JSON解码为数组

Can someone help me with json decoding

<?php

 //build query
$query = 
  "SELECT 
  userid, 
  username, 
  password, 
  email 
  FROM Users ORDER BY userid";

$results = mysqli_query($connection,$query);
$arRows = array();

while ($row = mysqli_fetch_assoc($results)) {
  array_push($arRows, $row);
}

$results = mysqli_query($connection,$query);
echo json_encode($arRows);
$encode = json_encode($arRows);

?>

This is the array which is encoded, now I want it decoded.

add

$decode = json_decode($encode, true);

and $decode will be an array. :)