    function delete_recurring() {
        $item = $this->event->find('first', 'id=' . $this->params['id']);
        if ($item->is_recurring == 1) { // need to give user options
            expHistory::set('editable', $this->params);
            assign_to_template(array(
                'checked_date' => $this->params['date_id'],
                'event'        => $item,
            ));
        } else { // Process a regular delete
            $item->delete();
        }
    }

The software constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component.