Re: SPARQL results in RDF

On 09/25/2013 04:02 PM, Dave Reynolds wrote:
> On 25/09/13 14:57, Sven R. Kunze wrote:
>> On 09/25/2013 03:53 PM, Dave Reynolds wrote:
>>> Hi Damian,
>>>
>>> On 25/09/13 14:16, Damian Steer wrote:
>>>> On 25/09/13 12:03, Stuart Williams wrote:
>>>>> On 25/09/2013 11:26, Hugh Glaser wrote:
>>>>>> You'll get me using CONSTRUCT soon :-)
>>>>>> (By the way, Tim's actual CONSTRUCT WHERE query isn't allowed 
>>>>>> because
>>>>>> of the FILTER).
>>>>>
>>>>> Good catch... yes - I've been bitten by that kind of thing too... 
>>>>> that
>>>>> not all that's admissible in a WHERE 'body', is admissible in a
>>>>> CONSTRUCT 'body'.
>>>>
>>>> As far as I'm aware it is -- Tim's original simply misplaced a curly
>>>> brace. The filter ought to be in the WHERE body.
>>>>
>>>> CONSTRUCT is essentially SELECT with a tabular data -> rdf system 
>>>> bolted
>>>> at the end of the pipeline.
>>>
>>> I think the point people were making is that the syntactic shortform
>>> "CONSTRUCT WHERE" with implicit template only applies when you have a
>>> simple basic graph pattern [1].
>>>
>>> If the WHERE clause is more complex, e.g. with a FILTER, then you need
>>> an explicit construct template.
>>>
>>> Dave
>>>
>>> [1] http://www.w3.org/TR/sparql11-query/#constructWhere
>>>
>>>
>>
>> How did you come to that conclusion?
>
> Based on the part of the specification given by link [1] above, which 
> says (my emphasis):
>
> "A short form for the CONSTRUCT query form is provided for the case 
> where the template and the pattern are the same and the pattern is 
> just a basic graph pattern **(no FILTERs and no complex graph patterns 
> are allowed in the short form)**."
>
> Dave
>

I see, Dave. However, my intention was to understand the reason behind 
that decision. This quote is not a justification, just a description of 
what's expected to work.

I can't see why restricting the set of where clauses is necessary.

-- 
Sven R. Kunze
Technische Universität Chemnitz
Department of Computer Science
Distributed and Self-organizing Systems Group
Straße der Nationen 62
D-09107 Chemnitz
Germany
E-Mail: sven.kunze@informatik.tu-chemnitz.de
WWW: http://vsr.informatik.tu-chemnitz.de/people/kunze
Phone: +49 371 531 33882

Received on Wednesday, 25 September 2013 14:11:04 UTC