[VCARDDAV] UID - why singular, not plural/ multiple?

"Andy Mabbett" <andy@pigsonthewing.org.uk> Sun, 25 July 2010 12:22 UTC

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Date: Sun, 25 Jul 2010 13:23:03 +0100
From: "Andy Mabbett" <andy@pigsonthewing.org.uk>
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Subject: [VCARDDAV] UID - why singular, not plural/ multiple?
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I notice that the latest draft says of UID:

   Purpose:  To specify a value that represents a globally unique
      identifier corresponding to the individual or resource associated
      with the vCard.

   Value type:  A single URI value.

   Cardinality:  (0,1)


Why is that a singular property? Why should a user not be able to record
more than one UID, where such exist?

For example, UIDs for the playwright William Shakespeare include:

   *   http://d-nb.info/gnd/118613723
   *   http://errol.oclc.org/laf/n78095332.html
   *   http://viaf.org/viaf/96994048
   *   http://dbpedia.org/page/William_Shakespeare
   *   ...

Have I misunderstood the purpose of UID?

Andy Mabbett