<?php
$servername = "yourServerName.com";
$username = "yourUserName";
$password = "yourPassword";
$dbname = "yourDatabaseName";

$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

$size = array(4,2,1);

$sql = "SELECT  userName, userContact FROM Persons";
$result = $conn->query($sql);

$response = array(
    "c2array" => true,
    "size" => $size,
    "data" => array()
);

while ( $row = $result->fetch_assoc() ) {
    $response['data'][] = array(
        array($row['userName']),
        array($row['userContact'])
    );
}

echo json_encode($response);
$conn->close();
exit();
?>