public function filterQuery(QueryBuilder &$query, &$selects = null)
    {
        //run the parent method
        parent::filterQuery($query, $selects);

        //if there is no value, return
        if (!$this->getOption('value')) {
            return;
        }

        $query->where($this->getOption('foreign_key'), '=', $this->getOption('value'));
    }