public function emptyDb()
    {
        if (($rows = $this->db->fetchRows('SHOW TABLES', [], true))) {
            $this->db->exec('SET foreign_key_checks = 0');
            foreach ($rows as $row) {
                $this->db->exec('DROP TABLE `' . $row[0] . '`');
            }
            $this->db->exec('SET foreign_key_checks = 1');
        }
    }