Hello Rob,
thank you for explaining the details.
Will obviously need to think of some other approach then…
Regards,
Bardo
On 18.05.17 15.44 Uhr, Rob Vesse wrote:
A variable in SPARQL is only ever bound to a single value. So the set of
results as a whole will be the totality of the collection but an individual row
in those results is a single item of that collection.
So essentially your construct clause create a new collection for each element
of the list which is clearly not what you want.
In the context of a construct query you can only reconstruct a collection if
you are able to structure your where clause such that you selected the entire
collection as a single row and then provided a construct template to export
it. Your use case may be better served with a describe query e.g.
DESCRIBE <http://resources.semaworx.eu/activity/user/BNNuserPAR>
Rob
On 18/05/2017 14:15, "Bardo Nelgen" <[email protected]>
wrote:
Hi Lorenz,
thanks for the clarification – but isn’t the Collection as a whole meant
to be the query result, rather than its various elements !??
Best,
Bardo
On 18.05.17 13.45 Uhr, Lorenz Buehmann wrote:
> Because in SPARQL there is always only a single resource bound to a
> variable, in your case ?member and not the whole list
>
>
> On 18.05.2017 12:18, Bardo Nelgen wrote:
>> Hi all,
>>
>> why does the CONSTRUCT SPARQL of
>>
>>> PREFIX rdf:<http://www.w3.org/1999/02/22-rdf-syntax-ns#>
>>> PREFIX xsd:<http://www.w3.org/2001/XMLSchema#>
>>> PREFIX as:<https://www.w3.org/ns/activitystreams#>
>>> PREFIX list: <http://jena.hpl.hp.com/ARQ/list#>
>>>
>>> CONSTRUCT {<http://resources.semaworx.eu/activity/user/BNNuserPAR>
>>> as:items ( ?members ) .}
>>>
>>> WHERE{<http://resources.semaworx.eu/activity/user/BNNuserPAR>
>>> as:items [ list:member ?members ] .}
>> produce
>>
>>> <rdf:Description
>>> rdf:about="http://resources.semaworx.eu/activity/user/BNNuserPAR";>
>>> <as:items rdf:parseType="Collection">
>>> <rdf:Description
>>>
rdf:about="http://resources.semaworx.eu/activity/user/BNNuserPAR/SHA512UIDdateUID004"/>
>>> </as:items>
>>> <as:items rdf:parseType="Collection">
>>> <rdf:Description
>>>
rdf:about="http://resources.semaworx.eu/activity/user/BNNuserPAR/SHA512UIDdateUID003"/>
>>> </as:items>
>>> <as:items rdf:parseType="Collection">
>>> <rdf:Description
>>>
rdf:about="http://resources.semaworx.eu/activity/user/BNNuserPAR/SHA512UIDdateUID002"/>
>>> </as:items>
>>> <as:items rdf:parseType="Collection">
>>> <rdf:Description
>>>
rdf:about="http://resources.semaworx.eu/activity/user/BNNuserPAR/SHA512UIDdateUID001"/>
>>> </as:items>
>>> </rdf:Description>
>> rather than
>>
>>> <rdf:Description
>>> rdf:about="http://resources.semaworx.eu/activity/user/BNNuserPAR";>
>>> <as:items rdf:parseType="Collection">
>>> <rdf:Description
>>>
rdf:about="http://resources.semaworx.eu/activity/user/BNNuserPAR/SHA512UIDdateUID004"/>
>>> <rdf:Description
>>>
rdf:about="http://resources.semaworx.eu/activity/user/BNNuserPAR/SHA512UIDdateUID003"/>
>>> <rdf:Description
>>>
rdf:about="http://resources.semaworx.eu/activity/user/BNNuserPAR/SHA512UIDdateUID002"/>
>>> <rdf:Description
>>>
rdf:about="http://resources.semaworx.eu/activity/user/BNNuserPAR/SHA512UIDdateUID001"/>
>>> </as:items>
>>> </rdf:Description>
>> ??
>>
>> It’s obviously not the same and caused by the iteration over the query
>> results.
>>
>> But how could I prevent it from happening without having to create a
>> separate query for the construction ?
>>
>> As always, input and references are highly appreciated.
>>
>> Regards,
>>
>> Bardo
>>
>>
>
