Whether this kind of idiom is acceptable RDF (I don't agree that it always is) it seems to me to be _terrible_ Linked Data. This is the opposite of allowing people to "follow their noses".
I think also that it is a little too blithe to rely on OWL inferencing to produce simple results from complex queries. OWL inferencing is fantastic technology but it is implemented very variously today. Some semantic frameworks have very full capabilities and some do not, and the extent to which their implementations are accessible of "tuning" vary as well. It doesn't seem at all to me like database tuning. It seems more like making assumptions on available SQL extensions. To be a little more specific about this, you could describe which OWL profile would be of interest and what kind of guarantees it could make around the extra time needed on the extension of a query.
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A. Soroka
The University of Virginia Library
On Jul 9, 2014, at 10:20 PM, Stuart Yeates <[log in to unmask]> wrote:
> On 07/10/2014 01:52 PM, Karen Coyle wrote:
>
>> I'm no expert in SPARQL, but I am going to presume that
>>
>> http://www.example.com/books/book1
>> a http://bibframe.org/vocab/Book .
>>
>> Will result in more retrievals on queries for things of type
>> http://bibframe.org/vocab/Book
>>
>> than
>>
>> _:bnode1 a bf:Instance ;
>> bf:uri _:bnode2 .
>> _:bnode2 a bf:Identifier ;
>> bf:identifierValue "http://www.example.com/books/book1" .
>>
>> In other words, the further down you bury the key information (the URI
>> for the thing) the less likely your data will be discovered and linked.
>
> My understanding is that if there is OWL logic available to the query engine that can be used to confirm these queries are the same, SPARQL should always return the same results for the two queries.
>
> There are, of course, questions of efficiency, but these are not essentially different to the current issues many of us face with tuning database queries for reports we run on our ILS's.
>
> cheers
> stuart
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