I have a problem on how to be able to tick the checkboxes chosen during registration.
If i will update 1 record for example a student, his/her chosen, example his/her interests will be ticked during update.
you can get the value ticket by $_POST['checkbox'] value..
What are you talking about when you say "tick the checkboxes during registration".
Nothing is ticked during an update. You tick the checkboxes - THEN you update, e.g. form submission or an ajax event.
Get the status of that check box from your DB table.You may be saved that in 0(not checked) or 1 (checked).Check this status when you update the profile. Exg:
<input type="checkbox" name="chkBx" <?php echo ($yourCheckBoxStatus== "0") ? 'checked="checked"' : '' ; ?> value="0" />