Re: ISSUE-20: SPARQL Update: Empty vs non-existent graphs

On 7 Jan 2010, at 21:06, Paul Gearon wrote:
>
>> Some related issues in update are about adding triples into an  
>> empty graph
>> vs a non-existent graph (does it automatically get created?)
>
> I'd rather not. If this is needed then it can be done with:
>  CREATE SILENT <uri>
>  INSERT DATA { GRAPH <uri> { triples } }

I have a very strong preference for not requiring an explicit CREATE,  
I've already encountered usecases where this makes things very  
annoying, e.g. I'd like to:

INSERT {
   GRAPH ?s { ?s ?p ?o }
}
WHERE {
   ?s a :Thing .
   ?s ?p ?o .
}

4store would require some work to detect new graph URIs being used,  
and explicitly create a graph, but I think it's worth it to avoid  
annoying users.

N.B. it's not necessary to detect removing the last triple from a  
graph, as that doesn't necessarily have to explicitly remove the graph.

- Steve

-- 
Steve Harris, CTO, Garlik Limited
2 Sheen Road, Richmond, TW9 1AE, UK
+44(0)20 8973 2465  http://www.garlik.com/
Registered in England and Wales 535 7233 VAT # 849 0517 11
Registered office: Thames House, Portsmouth Road, Esher, Surrey, KT10  
9AD

Received on Friday, 8 January 2010 11:10:08 UTC