private function _getData($primaryKey)
    {
        $table = $this->table;
        $db = $this->db;

        $query = "SELECT * FROM {$table->getTableName()} WHERE {$table->getPrimaryKey()} = $primaryKey";
        $sth = $table->getAdapter()->prepare($query);
        $sth->execute();

        return $sth->fetch($db::FETCH_ASSOC);
    }