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Re: IRI Templates

From: David Booth <david@dbooth.org>
Date: Fri, 21 Feb 2014 00:33:16 -0500
Message-ID: <5306E51C.4070008@dbooth.org>
To: Gregg Kellogg <gregg@greggkellogg.net>, Linked JSON <public-linked-json@w3.org>
Personally, I would prefer not to overload JSON-LD this way.  This 
essentially amounts to a transformation rule.  And although 
transformation rules are useful and neede, I would prefer to have them 
specified as a separate layer.

David Booth

On 02/20/2014 08:50 PM, Gregg Kellogg wrote:
> As part of work on the CSV WG, I've put forward the concept of CSV-LD
> [1]. As I've discussed before, the idea is to use something like a
> JSON-LD frame to map column values in a CSV to turn it into JSON-LD.
>
> I discussed the idea of IRI Templates (really @id templates) on the
> mailing list [2]. The idea is that fields in a CSV may be used to
> identify entities, but they may not explicitly include an identifier.
> In some cases, it may take two columns to determine a unique
> identifier, for example when a database dump has a composite primary
> key.
>
> The idea I had is that one or more column values might be used to
> create a template for an IRI or Blank Node. This concept might be
> more generally useful for JSON-LD framing, but I wanted to get some
> reaction from this list. From the email:
>
> [[[ I've been hand-waving around this, but one way to do this might
> be to extend the context definition to describe identifier
> templates:
>
> { "region_id": {"@id": "_:{Sales Region}", "@type": "@idTemplate"} }
>
> I'm sure we can do much better, but the basic idea is that column
> values can be used within a template used to construct an IRI or
> BNode identifier, using some suitable rules. We could then use
> "region_id" in the frame, with the understanding that it will be
> expanded using the template defined in the context.
>
> { "@id": "region_id", "@type": "ex:SalesRegion", "Sales Region":
> null, "ex:period": { "@type": "ex:SalesPeriod", "Quarter": null,
> "Sales": null } } ]]]
>
> The idea would be that if a term is of type @idTemplate, it could be
> used as a key or value (in this case, the value of @id), and it would
> be processed based on other properties of the associated node ("Sales
> Region" here). Obviously, this would require some normalization as
> well, so that the result would be legal. A more complete example
> would be the following:
>
> { "@context": { "dc": "http://purl.org/dc/terms/", "rdf":
> "http://www.w3.org/1999/02/22-rdf-syntax-ns#", "ex":
> "http://example/", "Sales Region": "dc:title", "Quarter":
> "dc:title", "Sales": "rdf:value", "region_id": {"@id": "_:{Sales
> Region}", "@type": "@idTemplate"} }, "@id": "region_id", "Sales
> Region": null, "ex:period": { "Quarter": null, "Sales": null } }
>
> I suppose that filling in the template term would be part of
> compaction, and the @idTemplate would allow such a term to be used as
> the value of @id. This could presumably be done in a CSV-LD spec, but
> it might be more generally useful as part of JSON-LD Framing.
>
> Thoughts?
>
> Gregg Kellogg gregg@greggkellogg.net
>
> [1] https://www.w3.org/2013/csvw/wiki/CSV-LD [2]
> http://lists.w3.org/Archives/Public/public-csv-wg/2014Feb/0119.html
>
>
>
Received on Friday, 21 February 2014 05:33:45 UTC

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