Re: New cast between inet/cidr and bytea

Tom Lane írta:
> Zoltan Boszormenyi <zb@cybertec.at> writes:
>   
>> Bruce Momjian írta:
>>     
>>> What is the use case for such a cast?
>>>       
>
>   
>> The application doesn't want to parse the textual IP address
>> when all the parsing and checking intelligence is already there
>> in the inet/cidr type checks.
>>     
>
> This presumes exactly the assumption we are questioning, namely that
> there's a universal binary representation for these things.

But there is: network order.

>   There might
> be such for bare IP addresses (ignoring endianness) but the argument
> doesn't scale to CIDR.

Would you enlighten me why not?

>   You've also failed to make the case that this
> application designer has made a sane judgment about whether avoiding
> parsing is a good tradeoff here.
>   

So, reinventing the wheel is always the way to go?
Even when the app is actually storing those IP addresses
with the type and features PostgreSQL provides?

> Also: to the extent that the application is willing to deal with a
> Postgres-specific inet/cidr representation (which, in the end, is
> what this would be) it can do that *today* using binary output format.
> So I'm still not seeing an argument for exposing a cast to bytea.
>
>             regards, tom lane
>   

But the binary output of inet/cidr needs another round of parsing
which requires using internal server headers.

Would you like a 4/8/16/32 byte output using IP only
or IP + fully represented netmask better?

Best regards,

-- 
----------------------------------
Zoltán Böszörményi
Cybertec Geschwinde & Schönig GmbH
http://www.postgresql.at/