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Message-ID: <a2de01dd0510190019v54de5097i@mail.gmail.com>
Date: Wed, 19 Oct 2005 08:19:04 +0100
From: Peter Childs <peterachilds@gmail.com>
To: pgsql-performance@postgresql.org
Subject: Re: Inefficient escape codes.
In-Reply-To: <20051018204727.GA29110@winnie.fuhr.org>
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References: <3cf983d0510181107sb060171je702da5fe0c29252@mail.gmail.com>
	<20051018190324.GA92715@winnie.fuhr.org>
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	<20051018204727.GA29110@winnie.fuhr.org>

On 18/10/05, Michael Fuhr <mike@fuhr.org> wrote:
> [Please copy the mailing list on replies so others can participate
> in and learn from the discussion.]
>
> On Tue, Oct 18, 2005 at 07:09:08PM +0000, Rodrigo Madera wrote:
> > > What language and API are you using?
> >
> > I'm using libpqxx. A nice STL-style library for C++ (I am 101% C++).
>
> I've only dabbled with libpqxx; I don't know if or how you can make
> it send data in binary instead of text.  See the documentation or
> ask in a mailing list like libpqxx-general or pgsql-interfaces.
>
> > > Binary transfer sends data in binary, not by automatically converting
> > > to and from text.
> >
> > Uh, I'm sorry I didn't get that... If I send: insert into foo
> > values('\\001\\002') will libpq send 0x01, 0x02 or "\\\\001\\\\002"??
>
> If you do it that way libpq will send the string as text with escape
> sequences; you can use a sniffer like tcpdump or ethereal to see this
> for yourself.  To send the data in binary you'd call PQexecParams()
> with a query like "INSERT INTO foo VALUES ($1)".  The $1 is a
> placeholder; the other arguments to PQexecParams() provide the data
> itself, the data type and length, and specify whether the data is in
> text format or binary.  See the libpq documentation for details.
>

You could base64 encode your data admitiaddly increasing it by 1/3 but
it does at least convert it to text which means that its more
unserstandable. base64 is also pritty standard being whats used in
EMails for mime attachments.

Peter