RE: SPARQL performance for ORDER BY on large datasets



> -----Original Message-----
> From: Andreas Langegger [mailto:al@jku.at]
> Sent: 27 August 2009 10:04
> To: Bernhard Schandl; Semantic Web; Seaborne, Andy
> Subject: Re: SPARQL performance for ORDER BY on large datasets
> 
> Hi Bernhard,
> 
> yes. That would be an option... or putting all in a RDBMS and use
> Virtuoso RDF views or D2R. But I think it's too long-winded having to
> control some RDBMS-like schema if you're working with native RDF data.
> I would expect a more RDF-centric way where I can define indexes on
> subsets of triples, e.g. grouped by properties, etc. Would this be
> possible to implement for, let's say, Jena/TDB?

Yes - it's possible to implement.  It's something I have wanted to do for a while now.

 Andy

> 
> Regards,
> Andy
> 
> On Aug 27, 2009, at 9:32 AM, Bernhard Schandl wrote:
> 
> > Hi,
> >
> >> I'm wondering for some time already if there is any triple store
> >> that allows to define custom indexes on special predicates or
> >> subsets of the whole set of triples/quads? All the existing stores
> >> I know index over all triples in different combinations (spo,
> >> pso, ...). Is there any research going on towards partial indexes
> >> over user-defined subsets of triples? E.g. an index over all
> >> xsd:dateTime literals.
> >
> > some time ago I was looking for triple stores that allow to
> > customize the database schema, e.g., that allow me to specify
> > something like "I want all foaf:Person resources together with their
> > foaf:firstName and foaf:surname stored in a designated (optimized)
> > table." If you are aware of any triple store aware of that
> > functionality I would be happy to know.
> >
> > Best, Bernhard
> >
> 
> 
> http://www.langegger.at

> ----------------------------------------------------------------------
> Dipl.-Ing.(FH) Andreas Langegger
> FAW - Institute for Application-oriented Knowledge Processing
> Johannes Kepler University Linz
> A-4040 Linz, Altenberger Straße 69
> 
> 
> 
> 
>

Received on Thursday, 27 August 2009 09:53:29 UTC