Update Multiple rows at one time in PHP - php

Question

I am trying to update multiple rows on submit of a form (in particular this one is the "hours" field.
I have it working but only one of the value updates vs all of them.
There is the possibility of having different values for each update.
The form code:
$query2 = "select * FROM work_hours WHERE formid = $formid ";
$result = $mysqli->query( $query2 );
$num_results = $result->num_rows;
if( $num_results > 0){
echo " <table border='0' align='center'>
<tr>
<td colspan='2' align='center'>
<strong> Time Away Break Down</strong>
</td>
</tr>
<tr>
<td align='center'>Date</td>
<td align='left'>Hours</td>
</tr>";
while( $row = $result->fetch_assoc() ){
extract($row);
echo " <tr>
<td class='hidden_sm' align='center'>
<input type='text' name='id' size='10' value='$id' class='dept' readonly style='width:30px;'>
<input type='text' name='date' size='40' value='$date' class='dept' readonly> <input type='text' name='end_date' size='40' value='$end_date' class='dept' readonly>
</td>
<td class='hidden_sm' align='left' >
<input type='text' name='hours' size='10' style='width:30px;' value='$hours' class='dept' >
</td>
</tr>
";
}
echo "<tr>
<td colspan='2' align='center'>
<input type='submit' name='Submit' value='Submit Request'>
</td>
</tr>
</form>
</table>";//end table
Submit Code:
$id = $_POST['id'];
$formid = $_POST['formid'];
$hours = $_POST['hours'];
include 'connect-db.php';
$stmt = $mysqli->prepare("UPDATE work_hours SET hours = ? WHERE formid = ?");
$stmt->bind_param('si',
$_POST['hours'],
$_POST['formid']);
$stmt->execute();
if ( $stmt ) {
echo "<p align='center'>Thank you, this request has been approved.<BR>You will be redirected in 5 seconds</p>";
} else {
echo "Error, you status cannot be updated. <BR> Please contact your system administrator.";
}
$stmt->close();
?>
Could anyone point me in the right direction to have all values update on submit, as I have had zero luck.
As well I do understand the need to prevent SQL Injections, and that I am working, so no need to remind me.
Thanks in advance!

Answer 1

Looks like you'll want to use a CASE statement as explained here:
How does MySQL CASE work?
Use a loop to build the statement and you're better off using the id as the identifier instead of formid, since the id is the unique value and you could have different results in the form.