Re: convert int to bytea

On Nov 29, 2007 9:35 PM, Zoltan Boszormenyi <zb(at)cybertec(dot)at> wrote:

> Hi,
>
> please don't top post to someone who didn't used this convention
> in answering you. It's impolite. I edited the mail a bit to return sanity.
>
> > On Nov 29, 2007 9:00 PM, Douglas McNaught <doug(at)mcnaught(dot)org
> > <mailto:doug(at)mcnaught(dot)org>> wrote:
> >
> > On 11/29/07, ohp(at)pyrenet(dot)fr <mailto:ohp(at)pyrenet(dot)fr>
> > <ohp(at)pyrenet(dot)fr <mailto:ohp(at)pyrenet(dot)fr>> wrote:
> >
> > > On Thu, 29 Nov 2007, Gregory Stark wrote:
> > >
> > > > What do you want the resulting bytea to look like?
> > > >
> > > example : id = 9 , bytea = '\000\000\011' IIRC
> >
> > What do you expect to happen when server and client are
> > differently-endian?
> >
> > -Doug
> >
>
> Usama Dar írta:
> > Does it matter if you have written an explicit cast for int to bytea?
> >
>
> You don't know what't endianness is, do you?
> Say, you have a number: 0x12345678.
> This is stored differently depending on the endianness.
>
> Big-endian (like Sparc, Motorola, etc):
> 0x12 0x34 0x56 0x78
>
> Little-endian (Intel-compatibles, etc):
> 0x78 0x56 0x34 0x12
>
> So, how do you want your number to come out as a byte array?
> Since a bytea is a sequence of bytes as stored in memory,
> you may have different meaning for an int->bytea conversion.
>
> It's your homework to look up what's "network order" is. :-)
> But it would give you consistent answer no matter
> what CPU your server uses.
>

1) i wasn't aware people are sensitive to top email reply vs inline,
apologies if it offended you

2) i know what a byte order is , i just thought your interface i.e. libpq
would convert it to the local byte order.

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

--
Usama Munir Dar http://linkedin.com/in/usamadar
Consultant Architect
Cell:+92 321 5020666
Skype: usamadar