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Re: Dataset Syntax - checking for consensus

From: Gavin Carothers <gavin@carothers.name>
Date: Tue, 25 Sep 2012 19:47:59 -0700
Message-ID: <CAPqY83wL5fSsoVtmKvwFFUuWthiF=k2PfggZk7dm0dJGW=Jn1A@mail.gmail.com>
To: Sandro Hawke <sandro@w3.org>
Cc: W3C RDF WG <public-rdf-wg@w3.org>
On Tue, Sep 25, 2012 at 4:14 PM, Sandro Hawke <sandro@w3.org> wrote:
> I'm not sure how much progress we'll be able to make on dataset semantics
> tomorrow, so I thought I'd draft some proposals on dataset syntax.   The
> chairs can put this on the agenda is they like (but it's too short notice
> for these decisions to be binding yet).  I'm thinking it would be useful to
> see how close we are to agreement on these issues.
>
> If you followup with votes, please use -1 for Formal Objection, 0 for
> abstain, +1 for approve.   Numbers in between are fine, too.
>
> PROPOSED: We will produce a W3C Recommendation for a dataset syntax, similar
> to TriG and to SPARQL's named graph syntax.

+1

>
> PROPOSED: We'll request a media-type for this syntax which is different from
> the media-type for Turtle.  (That is, we will not consider this language to
> supplant Turtle and take over the name, becoming the new "Turtle", as was
> once proposed.)

+1

>
> PROPOSED: Our dataset syntax will allow for the expression of empty named
> graphs, whatever their semantics might be (to be decided). The syntax is an
> empty curly-braces expression, as in "<g> { }".

0, all empty graphs are clearly isomorphic with all other empty
graphs... in fact I have no idea what an empty graph is. SPARQL
doesn't seem to know either? Seem to eliminate quad based syntaxes or
implementations. The idea "There is a graph here which may contain
something in the future" seem better expressed by something along the
lines of <g> { [] rdf:value [] } or I don't know, this is making my
brain hurt.

>
> PROPOSED: Our dataset syntax will have some standard mechanism (to be
> determined within the next few weeks) through which a Dataset serialization
> can include some RDF data about the Dataset (that is, some metadata in the
> form of an RDF graph).

-0.5 Exactly what this isn't just another graph is confusing to me

>
>
> Below, there are groups of proposals which are alternative solutions to a
> design issue.   If you approve of more than one of the alternatives, please
> vote "+2" for your favorite.
>
> * Name of the dataset syntax
>
> PROPOSED: We will call our recommended dataset syntax "trig", capitalized to
> Trig as needed.

0

> PROPOSED: We will call our recommended dataset syntax "TriG", but informally
> and in the media type, "trig".

+0

> PROPOSED: We will call our recommended dataset syntax "TriG", and use that
> capitalization everywhere.

-0

>
> * Use of equals sign, like <g> = { <s> <p> <o> } .  This is not in SPARQL
> but is in traditional TriG, for compatibility with N3.

N3 = does not mean TriG = .

>
> PROPOSED: In our dataset syntax, a "=" MAY appear between the name and the
> graph.

-0.9, implies an equality relationship from N3, is NOT an equality
relationship. Adds extra syntax for no real reason.

> PROPOSED: In our dataset syntax, a "=" MUST appear between the name and the
> graph.

-1

> PROPOSED: In our dataset syntax, a "=" MUST NOT appear between the name and
> the graph.

+1

>
> * Use of the "graph" keyword, which MUST be used in SPARQL and MUST NOT be
> used in traditional TriG.
>
> PROPOSED: In our dataset syntax, the case-insensitive keyword "graph" MAY
> appear before the name, in a name-graph pair.

-0.5 The whole syntax is about graphs, why do I need to say graph a lot?

> PROPOSED: In our dataset syntax, the case-insensitive keyword "graph" MUST
> appear before the name, in a name-graph pair.

-1

> PROPOSED: In our dataset syntax, the case-insensitive keyword "graph" MUST
> NOT appear before the name, in a name-graph pair.

+1

>
> * Use of curly braces { <a> <b> <c> } around the default graphs.   They MUST
> be used in traditional TriG, and MUST NOT be used in SPARQL.
>
> PROPOSED: In our dataset syntax, triples of the dataset's default graph MAY
> be surrounded by curly braces.

-0

> PROPOSED: In our dataset syntax, triples of the dataset's default graph MUST
> be surrounded by curly braces.

-0

> PROPOSED: In our dataset syntax, triples of the dataset's default graph MUST
> NOT be surrounded by curly braces.

-1

Prefer:
@default or DEFAULT <graph-iri>

>
> * Some designs for carrying for metadata
>
> PROPOSED: In our dataset syntax, we'll say that metadata goes in the default
> graph

-0.5 see above, there shouldn't be a magic graph

> PROPOSED: In our dataset syntax, we'll say that the default graph goes
> inside curly braces and the metadata goes outside curly braces

-0.5

> PROPOSED: In our dataset syntax, we'll say that metadata goes inside a set
> curly braces after a keyword "meta".

-0.5

> PROPOSED: In out dataset syntax, we'll have a keyword "meta" followed by
> "default" or the name of a named graph, to indicate to readers where the
> metadata is.

-0.5
Received on Wednesday, 26 September 2012 02:48:27 GMT

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