$user_id = $_GET["userid"];
$groupid = $_GET["group"];


echo('<table border="1">'."n");
echo('<tr><th></th>');
$weekModifier = 0;
$date = new DateTime();

if($date->format('N') !== 1) {
    $date->sub(new DateInterval('P'. $date->format('N') . 'D'));
}

$interval = new DateInterval('P'.abs($weekModifier).'W');

if($weekModifier > 0) {
    $date->add($interval);
} else {
    $date->sub($interval);
}

for($i = 1; $i <= 7; $i++) {
    echo "<th>" . $date->add(new DateInterval('P1D'))->format('d-m') . "</th>";
}

echo "</tr>";

$stmt = $dbh->query("SELECT fullname, name FROM people, shifts WHERE group_id=$groupid AND shift_id IN (SELECT shift_id FROM shift_assigned WHERE (user_id=$user_id AND day_id=8))");

while ( $row = $stmt->fetch(PDO::FETCH_ASSOC) ) {
    echo "<tr><td>";
    echo(htmlentities($row['fullname']));
    echo "</td><td>";
    echo(htmlentities($row['name']));
    echo "</td><td></td><td></td><td></td><td></td><td></td><td></td></tr>";

}
echo "</table>";