public function get(string $name = null): DatabaseConnection
    {
        if (null == $name) {
            $name = DatabaseConfiguration::DEFAULT_ID;
        }

        if (isset($this->connections[$name])) {
            return $this->connections[$name];
        }

        $this->connections[$name] = new PdoDatabaseConnection(
                $this->configurations->get($name)
        );
        return $this->connections[$name];
    }