MySQL UPDATE not working? - php

Question

I'm making a site where the owner has to be able to update their events, but my update code isnt working even though im 99% sure I havent made any errors.
First the form where you press update:
<?php
$sql = "SELECT * FROM events ORDER BY id ASC";
$res = $objCon->query($sql) or die('fejl i query:'.mysqli_error($objCon));
while($row=$res->fetch_array()) {
$id = $row['id'];
echo "<div class='eventpost'>";
echo "<div class='dato'>";
echo $row['id'];
echo "</div>";
echo "<p class='overskrift'>";
echo "<a href='update.php?id=$id'>RET </a>";
echo "<a href='code_delete.php?id=$id'>SLET</a>";
echo $row['overskrift'];
echo "</p>";
echo "</div>";
}
?>
then the update form:
<form action="code_update.php" method="POST">
<label>Dato:<br>
<input type="text" name="dag" value="<?php echo $data['dag']; ?>"></label>
<label>Månede:<br>
<input type="text" name="month" value="<?php echo $data['month']; ?>"></label>
<label>Overskrift:<br>
<input type="text" name="overskrift" value="<?php echo $data['overskrift']; ?>"></label>
<label>Tekst:<br>
<input type="text" name="tekst" value="<?php echo $data['tekst']; ?>"></label>
<input type="hidden" name="id" value="<? echo $id; ?>">
<input type="submit" value="Opret">
</form>
and finally the update code
<?php
session_start();
if($_SESSION['auth'] == 2){
include('incl_db.php');
$id = $_POST['id'];
$overskrift = $_POST['overskrift'];
$dag = $_POST['dag'];
$month = $_POST['month'];
$tekst = $_POST['tekst'];
$sql = "UPDATE events SET overskrift='$overskrift', dag='$dag', month='$month', tekst='$tekst' WHERE id='$id'";
$res = $objCon->query($sql);
header('location:events.php');
}else{
header('location:index.php');
}
?>

Answer 1

Probably shorthand tags are disabled in your php version.So try changing this
<input type="hidden" name="id" value="<? echo $id; ?>">
to this
<input type="hidden" name="id" value="<?php echo $id; ?>">
You can check this answer for more.