Refining Jonathan's point, though I too would accept the original:
I like the concept of merging, though merging the authority and the ID per the example makes it more likely that only a human can process the identifier (where does the authority stop and the identifier start?). The world of the web is moving toward open linked data, and it would be nice to enable that wherever possible.
It seems useful if the user can be sure the ID is really an ID, meaning unique and unambiguous, but this is hard if the format isn't precisely specified. (Is '001' a different ID than '1'? Not clear.)
One way to put the authority into the ID string and maintain an identifier that is verifiable is to use (require) URIs. This guarantees uniqueness, precise authority determination, and computability in a way that a string like "wmo station id 03808" can not. (With some URI types dereferencing is also possible, but maybe we don't want to go so far as all that!)
Yes, this enforces some (fairly trivial) work on the provider. But only on those providers who already think providing a unique platform identification is important, so I think they would be receptive to this approach.
These may be comments to be made to NACDD/UDDC as well, but if CF is going to recommend an approach, it may provide an opportunity to make it maximally effective.
john
On Sep 15, 2011, at 06:25, Jonathan Gregory wrote:
> Dear Jeff
>
>> platform_primary_id: variable of character type containing an ID or
>> name of an observing station or other platform
>> platform_primary_id_authority: variable of character type,
>> specifying the naming authority or system used to choose
>> platform_primary_id
>> platform_secondary_id: variable of character type containing a
>> second ID or name of an observing station or other platform.
>> platform_primary_id must be present.
>> platform_secondary_id_authority: variable of character type,
>> specifying the naming authority or system used to choose
>> platform_secondary_id
>> platform_description: variable of character type which describes an
>> observing station or other platform
>
> I think these are OK, thanks.
>
> Still, I'd like to suggest something different - not necessarily arguing
> for it, but just as an idea. The authority seems to be metadata about metadata
> i.e. you can't understand the ID without the authority. If that is so, could
> we put the authority and the ID in the same string e.g. "WMO station id 03808"?
> Since we're not standardising the format of the ID and authority strings, I
> don't these attributes could be processed automatically anyway, so really they
> are a long_name for the platform. Again, if they are not standardised, why not
> put primary, second (and any other) IDs all in the same string? Unless we have
> standard rules for the contents and purposes of the various attributes to
> make sure they are used consistently, I am not sure it helps to split up the
> information in this way. Perhaps this would be just as good:
>
> platform_name="cambourne"
> platform_id="wmo station id 03808, midas station number 1395"
>
> Probably there are good arguments against this which I have missed, and people
> may have good use cases for separate attributes.
>
> Best wishes
>
> Jonathan
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John Graybeal <mailto:jgraybeal at ucsd.edu>
phone: 858-534-2162
Product Manager
Ocean Observatories Initiative Cyberinfrastructure Project:
http://ci.oceanobservatories.org
Marine Metadata Interoperability Project:
http://marinemetadata.org
Received on Thu Sep 15 2011 - 10:01:05 BST
