data.php

<?php
    header('Content-Type: application/json');

    //SQL-information
    $dbservername = "d0020e.noexit.tv";
    $dbusername = "d0020e_data";
    $dbpassword = "hidden";
    $dbname = "d0020e_data";

    //Create new mysql connection
    $conn = new mysqli($dbservername, $dbusername, $dbpassword, $dbname);

    if ($conn->connect_error) {
        die("Connection failed: " . $conn->connect_error);
    }
    else
    {
        if(isset($_GET['n'])){

            if($_GET['n'] == all) {
                //Query all points
                $sql = "SELECT * FROM test_dp ORDER BY tstamp DESC";
            }
            else {
                //Query n number of points
                $limit = intval($_GET['n']);
                $sql = "SELECT * FROM test_dp ORDER BY tstamp DESC LIMIT $limit";
            }
        }
        else {
            //n is not set, query a default number of 360 points
            $limit = 360;
            $sql = "SELECT * FROM test_dp ORDER BY tstamp DESC LIMIT $limit";
        }
        $data_points = array();
        $result = $conn->query($sql);

        //Add all points to array and echo in JSON format
        while($row = $result->fetch_assoc())
        {
            $point = array("x" => $row['tstamp'] , "y" => $row['y']);
            array_push($data_points, $point);
        }
        echo json_encode($data_points, JSON_NUMERIC_CHECK);
    }
    $conn->close();
?>