Hi Vicenç. Please consider the concept of "unique identifier"[1]. The only purpose it has is that it must be able to uniquely identify an entity, in this case a momument. A uniquely identified monument can have multiple properties. One of those could be the country it is in (or normalised a country id which is the unique identifier of a country name), or a reference to a unique identifier in a country's system, a municipality's system or an autonomous region's system for monuments.
Unique identifiers are completely trivial and the only requirement is that they are unique and that you do not run out of them before your collection is complete. Unique identifiers are usually optimised for data processing, and databases index integers usually pretty well.
Cheers!
Siebrand
[1] http://en.wikipedia.org/wiki/Unique_identifier
Van: Vicenç Riullop vriullop@hotmail.com Beantwoorden - Aan: Wiki Loves Monuments Photograph Competition wikilovesmonuments@lists.wikimedia.org Datum: Sun, 13 Mar 2011 16:01:02 +0000 Aan: wikilovesmonuments@lists.wikimedia.org Onderwerp: [Wiki Loves Monuments] Unique identifiers
I have some doubts about the identifiers. How will we distinguish if monument number 50 is from Nederland or Andorra? Perhaps should it be identified with a prefix (NL-50, AD-50), or perhaps is there any solution in mind?
Moroever, in Spain we can find different formats in different sources: "(R.I.) - 51 - 0010580 - 00000", "R-I-51-0010580", and others. Obviously we need to unify to an unique format and we are discussing it with wm-es, but I would appreciate some inputs. "R.I." or "R-I" stands for Registro de Inmuebles (buildings' register) and "51" is the category for monuments. Probably it is not a good idea to ask participants to type a complicated number format with spaces, zeros, etc. One solution is to reduce it to its numeric form "10580" or perhaps to construct a simplified format like "RI510010580". What are the technical implications about identifiers, and which would be the best approach?