Date: Tue, 17 Apr 2007 16:53:18 -0400
From: Andrew Sullivan <ajs@crankycanuck.ca>
To: pgsql-sql@postgresql.org
Subject: Re: Floating point type to store numbers
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On Tue, Apr 17, 2007 at 04:33:33PM -0400, Radhika Sambamurti wrote:
> Andrew,
> This has been quite helpful. My main concern is CPU cost.  Thanks for the
> input.

You're welcome.  Are you sure your main concern should be CPU cost?
It's true that numeric is more costly that float in a lot of cases,
but I know at least one auditor who will refuse to certify results
from programs that anywhere use floating-point storage or calculation
on accounting data.  The problem is really that you can get compound
errors -- very small rounding errors several times can turn out to be
a big problem.  (One quick primer that can help you understand this
is at <http://www2.hursley.ibm.com/decimal/decifaq1.html>.)

A
-- 
Andrew Sullivan  | ajs@crankycanuck.ca
The whole tendency of modern prose is away from concreteness.
		--George Orwell