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Re: REDUCED and the SPARQL XML Results Format

From: Seaborne, Andy <andy.seaborne@hp.com>
Date: Mon, 26 Mar 2007 12:25:16 +0100
Message-ID: <4607AD9C.3070101@hp.com>
To: Steve Harris <steve.harris@garlik.com>
CC: dawg mailing list <public-rdf-dawg@w3.org>



Steve Harris wrote:
...
>> Subsidiary questions:
>>
>> If there is way to indicate "reduced", and the service  
>> implementation of REDUCED is to do "all" for this service request,  
>> can the service just omit the reduced because results are all present?
>>
>> If there is way to indicate "reduced", and the service  
>> implementation of REDUCED is to do DISTINCT?  Is it permissible to  
>> set the 'distinct' attribute true? Woudl we recommended to doing so?
> 
> FWIW, my preference is to not explicitly flag REDUCED result sets as  
> such.
> 
> Whether the distinct attribute should be set where appropriate is an  
> interesting question. It also applies to SPARQL services that  
> currently implicitly DISTINCT.

I don't see much use for a distinct attribute (I do see more utility for the 
'ordered').


There never was anything stated about implicitly DISTINCT - I've always seen 
it as a local API issue where the local API inserts (or has the effect of 
inserting) DISTINCT into all queries.  It was the case the test suite 
carefully didn't distinguish - except we let such a test case in which is what 
started all this latest stuff into motion.

With the introduction of REDUCED, and the algebra, this all looks a bit more 
suspect.  REDUCED is used when the query is unconcerned about cardinality. 
So, by implication only, SELECT without modifier is suggesting complete 
cardinality.

	Andy

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Received on Monday, 26 March 2007 11:25:34 GMT

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