That's very, very unfortunate. Do you know why those aggregate functions 
are not supported?

Without aggregation performed at the source of the data, more data than 
necessary has to be transfered over to the sink. The larger the data set 
(the more useful aggregation is), the larger the transfer. The lack of 
support for aggregation pretty much cripples any advanced browsing 
functionality on top of SPARQL data sources.

The first draft of SPARQL was in October 2004 [1]. I remember informally 
suggesting adding aggregate functions to it in Summer/Fall 2006.

David
[1] http://www.w3.org/TR/2004/WD-rdf-sparql-query-20041012/

Brian Caruso wrote:
> The 2008 SPARQL recommendation definitely doesn't support COUNT and I don't
> think it supports MIN, MAX or what you would think of as a SQL style
> GROUP BY.
>
>
> David Huynh wrote:
>   
>> Right now server-side Backstage formulates its queries to the 
>> triple store by putting together Sesame "query algebra trees". If SPARQL 
>> is as expressive as Sesame's query algebra (supporting GROUP, COUNT, 
>> MIN, MAX), then it shouldn't be hard to swap in a SPARQL end point
>>   
>>     
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