- From: David Booth <david@dbooth.org>
- Date: Mon, 14 Oct 2013 13:23:40 -0400
- To: Antoine Zimmermann <antoine.zimmermann@emse.fr>, semantic-web@w3.org
Interesting trick! I wouldn't want to use it in practice (for performance reasons), but it is quite a creative use of SPARQL. Thanks for pointing it out. David On 10/14/2013 11:00 AM, Antoine Zimmermann wrote: > I suggest that you look at this answer by Joshua Taylor in Stackoverflow: > > stackoverflow.com/questions/17523804/is-it-possible-to-get-the-position-of-an-element-in-an-rdf-collection-in-sparql/17530689#17530689 > > > > It shows a pure SPARQL 1.1 query that returns all the elements of a list > ordered by their position in the list. Very nice trick. > However, it also shows that using this trick will blow up the execution > time when the number of elements increase, and a customised programmatic > solution is far more efficient in general. > > > > AZ. > > > > > > Le 11/10/2013 16:02, David Booth a écrit : >> rdf:Lists are notoriously difficult to use in SPARQL if one wishes to >> retain the *order* of the items in the list. James Leigh and David Wood >> made a nice proposal a few years ago to address this problem directly at >> the RDF level, >> http://www.w3.org/2009/12/rdf-ws/papers/ws14 >> but for whatever reasons, that work was not included in the charter of >> the current RDF working group. As a result people often use some other >> means of representing ordered lists in RDF, such as by [item, index] >> pairs. >> >> For those who use an alternate way to represent an *ordered* list of >> items in RDF (instead of rdf:List), I am wondering: >> >> 1. What *ordered* list representation do you prefer, and why? >> >> 2. Have there been any efforts toward standardizing alternative >> *ordered* list representations in RDF? E.g., has anyone written up a >> spec on how they prefer to do it? >> >> Thanks, >> David >> >> >
Received on Monday, 14 October 2013 17:24:08 UTC