As a first little php mysql project I made a web app to keep records of my lessons as a guitar teacher. I made a form to add new students, and every lesson I make a few notes about the content of the lesson in another form.
The lessons are individual. A colleague would like to use the system, but his lessons are not individual. He has groups of 3 or 4 students.
I made a new table 'groups', a form to add a new group, and added a row 'group_id' in the student table. On my student_update page, I would like to add a select option to add a student to a group.
This is the code of the student_update page:
<?php
$q = "SELECT * FROM students WHERE uid = '$user[uid]' ORDER BY st_last ASC";//enkel velden ophalen van uid in kwestie
$r = mysqli_query($dbc, $q);
if (mysqli_num_rows($r) > 0) {
echo "<p>Om gegevens te wijzigen of aan te vullen kunt u gewoon in het desbetreffende veld typen en vervolgens op 'update' klikken.</p></br></br>
<table class='table'>
<thead>
<tr>
<th>Naam</th>
<th>Voornaam</th>
<th>Graad</th>
<th>Telefoon</th>
<th>Gsm</th>
<th>Email</th>
<th>Groep</th>
</tr>
</thead>";
while($student_list = mysqli_fetch_assoc($r)) { ?>
<tbody>
<form action="" method="POST" role="form">
<tr>
<input type="hidden" value="<?php echo $student_list['sid']?>" name="sid" />
<td width="8%"><input type="text" class="form-control" name="st_last" value="<?php echo $student_list['st_last']; ?>" /></td>
<td width="8%"><input type="text" class="form-control" name="st_first" value="<?php echo $student_list['st_first']; ?>"/></td>
<td width="3%"><input type="text" class="form-control" name="graad" value="<?php echo $student_list['graad']; ?>"/></td>
<td width="10%"><input type="text" class="form-control" name="vaste_telefoon" value="<?php echo $student_list['vaste_telefoon']; ?>"/></td>
<td width="10%"><input type="text" class="form-control" name="gsm" value="<?php echo $student_list['gsm']; ?>"/></td>
<td width="12%"><input type="text" class="form-control" name="email" value="<?php echo $student_list['email']; ?>"/></td>
<td width="11%"><div class="form-group">
<select class="form-control" name="groep" id="groep">
<option value="<>"></option>
<?php
$q2 = "SELECT * FROM Groepen ORDER BY groepsnaam ASC";
$r2 = mysqli_query($dbc, $q2);
while($groep_list = mysqli_fetch_assoc($r2)) {
?>
<option value="<?php echo $groep_list['groep_id']; ?>"><?php echo $groep_list['groepsnaam']; ?></option>
<?php } ?>
</select>
</div></td>
<td width="10%"> <div class="btn-group" role="group" aria-label="...">
<button type="submit" name="updatell" class="btn btn-warning">Update</button>
<button type="submit" name="deletell" class="btn btn-danger">Delete</button></td>
</tr>
</form>
</tbody>
<?php } }
else {
echo "U hebt nog geen leerlingen toegevoegd.";
}
?> </table>
And for the update:
<?php
if(isset($_POST['updatell'])) {
$qupdatestudent = "UPDATE students SET st_last='$_POST[st_last]', st_first='$_POST[st_first]', groep='$_POST[groep_id]', graad='$_POST[graad]', vaste_telefoon='$_POST[vaste_telefoon]', gsm='$_POST[gsm]', email='$_POST[email]' WHERE sid='$_POST[sid]'";
$r2 = mysqli_query($dbc, $qupdatestudent);
}
if(isset($_POST['deletell'])) {
$deletestudent = "DELETE FROM students WHERE sid='$_POST[sid]'";
$r3 = mysqli_query($dbc, $deletestudent);
}
?>
Everything worked fine until I added the group field. If I choose a group and hit update, I get the following error:
Notice: Undefined index: groep_id in /Applications/XAMPP/xamppfiles/htdocs/dummie/backend/leerlingenlijst.php on line 91
