GNU bug report logs - #6366
join can't join on numeric fields

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Message #21 received at 6366 <at> debbugs.gnu.org (full text, mbox):

From: Alex Shinn <alexshinn <at> gmail.com>
To: Jim Meyering <jim <at> meyering.net>
Cc: Pádraig Brady <P <at> draigbrady.com>, 6366 <at> debbugs.gnu.org
Subject: Re: bug#6366: join can't join on numeric fields
Date: Wed, 9 Jun 2010 16:33:06 +0900

On Wed, Jun 9, 2010 at 3:56 PM, Jim Meyering <jim <at> meyering.net> wrote:
>
> When comparing floating point numbers how would join measure equality?
> Should it consider 1.000000000000001e2 to be equal to 100.0 ?
> What if the maximum precision available does not
> allow us to distinguish those two values?

Indeed, that's why you generally don't use floating
point numbers as database keys.

We could either restrict the numbers to integers,
or continue to allow floats with a note to the effect
that float precision is machine-specific.  Personally
I have no need for floats so am happy with the former.

-- 
Alex

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