Message-ID: <49454298.3020202@boscorama.com>
Date: Sun, 14 Dec 2008 09:30:00 -0800
From: Bosco Rama <postgres@boscorama.com>
User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); en-US;
	rv:1.8.1.18) Gecko/20081030 SeaMonkey/1.1.13 Mnenhy/0.7.4.0
MIME-Version: 1.0
To: Bosco Rama <postgres@boscorama.com>, pgsql-interfaces@postgresql.org
Subject: Re: gcc _Decimal types & ecpg
References: <4941F4FB.1080902@boscorama.com>
	<20081214122646.GB30170@feivel.credativ.de>
In-Reply-To: <20081214122646.GB30170@feivel.credativ.de>
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit

Hi Michael,

Michael Meskes wrote:
> On Thu, Dec 11, 2008 at 09:22:03PM -0800, Bosco Rama wrote:
>> I was wondering if ecpg from Postgresql 8.3.5 is able to handle the gcc4 _Decimal32,
>> _Decimal64 & _Decimal128 intrinsic data types as transparently as the other types?
>> Or do they just end up getting treated as simple C float/double?
> 
> To be honest I haven't heard/thought about these datatypes before. Could you
> give me a pointer where to find more information? Are these types similar to
> our decimal/numeric types?

These are the Decimal Floating Point types with storage bit-widths of 32, 64, 128.
They are part of the IEEE-754 2008 spec and have been added to the C99 spec as an
extension and have been in gcc since early in the 4 series.  The GCC docs don't
have much on this:
  <http://gcc.gnu.org/onlinedocs/gcc/Decimal-Float.html>

But these guys do: <http://speleotrove.com/decimal>

I don't know how closely it would match your decimal/numeric types internally but
I believe you could specify matching NUMERIC(x,y) declarations for them.

> The parser does not recognize these type keywords. So yes, atm they have to be treated
> as float/double.

I wonder if there will be conversion/cast issues with that?  I'll have to look
closer to find out.  We may just end us storing them as text/varchar.

Thanks.

Bosco.