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Re: Should information be encoded into identifiers?

• From: "Christopher R. Maden" <crism@maden.org>
• To: "'xml-dev@lists.xml.org'" <xml-dev@lists.xml.org>
• Date: Sat, 06 Mar 2010 18:18:33 -0500

Michael Sokolov wrote:
> Basically I'm in favor of meaningless ids, because people will tend to find
> meaning in them even when told not too by folks like Michael.  But in our
> case, having the regional prefix, although it is in some sense meaningful,
> allows the ids to be maintained independently in two different systems. It
> also allowed us to have a mechanical renaming system so we didn't have to
> have an explicit mapping between two completely random sets of identifiers.

Two issues seem to have been conflated in Roger’s original post, and I
haven’t seen them explicitly separated in subsequent conversation.

One is the presence of meaning within the IDs, and the other is the use
of some characteristic for use as a namespace when allocating IDs.

For example, within an ISBN, the first numbers can be interpreted as
giving the publisher’s country, and with a US Social Security Number,
the first three numbers correspond to the region in which the number was
assigned.  But although one can, with some accuracy, infer meaning from
those numbers, the real reason for the scheme is to allocate namespaces
within which agencies can issue numbers without collision.

Mike’s post makes the relative virtues clear, at least to me: attempting
to have meaning in the IDs ended up failing, but having
collision-preventing namespace prefixes in the IDs eased generation.

~Chris
-- 
Chris Maden, text nerd  <URL: http://crism.maden.org/ >
“The honest man, though e’er sae poor, Is king o’ men for a’ that.”
 — Robert Burns, “Is There for Honest Poverty”
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• Follow-Ups:
  • Re: Should information be encoded into identifiers?
    • From: rjelliffe@allette.com.au

• References:
  • RE: Should information be encoded into identifiers?
    • From: "Michael Sokolov" <sokolov@ifactory.com>