Message-ID: <494D16E3.4030806@xs4all.nl>
Date: Sat, 20 Dec 2008 23:01:39 +0700
From: Jeroen Vermeulen <jtv@xs4all.nl>
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To: Whit Armstrong <armstrong.whit@gmail.com>
CC: pgsql-interfaces@postgresql.org
Subject: Re: simple example of copying data from a c/c++ array
 into postgres
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	<49413DE7.8040703@xs4all.nl>
	<8ec76080812110837y44785948gc9f367740c91071d@mail.gmail.com>
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Whit Armstrong wrote:
> Thanks, Jeroen.
> 
> just want to make sure I understand the convention for libpq and libpqxx.
> 
> the convention for getting data into postgres is to convert everything
> to strings first?  even if the data is already stored as a 64bit
> double in the client app?

Hi Whit,

Sorry for taking so long; for some reason my mail client doesn't seem 
convinced that I want to know about new mail in this mailbox.

The answer to your question is: yes, that is the default.  If you want 
to transfer binary data, it's still up to you to convert those doubles 
from your client's native format to the right format to transfer them in.

I've never used binary mode myself so I don't know off the top of my 
head what that format is--there's a good chance that all it takes is 
some variant of ntohl() but the details will depend on the architecture, 
OS, and possibly compiler (and/or compiler configuration) you work with.

Which by the way is one reason not to talk binary outside your 
application unless you have to!


Jeroen