Re: Backup Restore is Not Working

Further check through it seems that in this file course/classes/customfield/course_handler.php the function restore_instance_data_from_backup return the first custom field data id straightaway.

function restore_instance_data_from_backup(\restore_task $task, array $data) {
$courseid = $task->get_courseid();
$context = $this->get_instance_context($courseid);
$editablefields = $this->get_editable_fields($courseid);
$records = api::get_instance_fields_data($editablefields, $courseid);
$target = $task->get_target();
$override = ($target != \backup::TARGET_CURRENT_ADDING && $target != \backup::TARGET_EXISTING_ADDING);

foreach ($records as $d) {
$field = $d->get_field();
if ($field->get('shortname') === $data['shortname'] && $field->get('type') === $data['type']) {
if (!$d->get('id') || $override) {
$d->set($d->datafield(), $data['value']);
$d->set('value', $data['value']);
$d->set('valueformat', $data['valueformat']);
$d->set('valuetrust', !empty($data['valuetrust']));
$d->set('contextid', $context->id);
$d->save();
}
return $d->get('id');
}
}
}