[{"firstname":"Student","lastname":"1"},{"firstname":"Student","lastname":"2"},{"firstname":"Student","lastname":"3"}]

["85.00000","50.00000","90.00000"]

{"firstname":"Student","lastname":"1","grade":"85.00000"}

//Provisional Array Setup for Grades
$grade = array();
$userid = array();
$sqldata = array();

foreach($json_d->assignments[0]->grades as $gradeInfo) {
    $grade[] = $gradeInfo->grade;
    $userid[] = $gradeInfo->userid;
}

//Server Details
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "moodle";

// Create connection
$conn = mysqli_connect($servername, $username, $password, $dbname);

// Check connection
if (!$conn) {
    die("Connection failed: " . mysqli_connect_error());
}

foreach($userid as $id) {
        $sql = "SELECT firstname, lastname FROM mdl_user WHERE id='$id'";
        $result = mysqli_query($conn, $sql);

        if (mysqli_num_rows($result) > 0) {
        // output data of each row

            while($row = mysqli_fetch_array($result, MYSQL_ASSOC)) {
                $sqldata[] = $row;
            }

        } else {
            echo "ERROR!";
        }

}

$sqlr = json_encode($sqldata);
$grd = json_encode($grade);

echo $sqlr;
echo $grd;



mysqli_close($conn);