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Re: Formal objection to ISSUE-2 resolution

From: Richard Cyganiak <richard@cyganiak.de>
Date: Tue, 28 Jun 2011 19:44:35 +0100
Cc: RDB2RDF WG <public-rdb2rdf-wg@w3.org>
Message-Id: <0B557FF2-C077-459C-8649-CD0A9757F9C3@cyganiak.de>
To: David McNeil <dmcneil@revelytix.com>
Hi David,

On 28 Jun 2011, at 19:22, David McNeil wrote:
> [[
> RESOLUTION: R2RML is defined in terms of an input RDF graph. For interoperability simplicity, implementations SHOULD accept at least Turtle input.
> ]]
> 
> Richard - If the word "SHOULD" were changed to "MUST" would it be acceptable?

Well, let's not wordsmith the resolution but the spec.

It currently says in the intro:

[[
R2RML mappings are themselves expressed as RDF graphs and written down in Turtle syntax [TURTLE].
]]

and further down in the text:

[[
An *R2RML mapping* defines a mapping from a relational database to an RDF dataset. This mapping itself is represented as an RDF graph. In other words, RDF is used not just as the target data model of the mapping, but also as a formalism for representing the R2RML mapping itself. An RDF graph that represents an R2RML mapping is called a *mapping graph*.

An *R2RML mapping document* is any document written in the Turtle [TURTLE] RDF syntax that encodes an R2RML mapping graph. All examples throughout this specification use the Turtle syntax.
]]

So, the spec already defines the terms "R2RML mapping graph" and "R2RML mapping document". Currently, an RDF/XML document cannot be a conforming R2RML mapping document, but it can encode a conforming R2RML mapping graph.

Does adding this help?

[[
Conforming R2RML processors MAY accept R2RML mapping graphs encoded in other RDF syntaxes besides Turtle.
]]

Best,
Richard



> From the discussion that is what I think we were really talking about (despite what the formal resolution says). We were trying to make it agree with what you proposed last week.
> 
> -David
Received on Tuesday, 28 June 2011 18:45:05 GMT

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