- From: Eric Prud'hommeaux <eric@w3.org>
- Date: Mon, 14 Oct 2013 14:51:20 -0400
- To: Antoine Zimmermann <antoine.zimmermann@emse.fr>
- Cc: semantic-web@w3.org, david@dbooth.org
* Antoine Zimmermann <antoine.zimmermann@emse.fr> [2013-10-14 17:00+0200] > 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 Excellent! Though in all humility, we have to admit that what's cool about it is that it makes RDF lists as useful as OLO¹ and other graph schemas that tie an element to some sort of ordinal value. ¹<http://smiy.sourceforge.net/olo/spec/orderedlistontology.html> > 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 > > > > > > -- > Antoine Zimmermann > ISCOD / LSTI - Institut Henri Fayol > École Nationale Supérieure des Mines de Saint-Étienne > 158 cours Fauriel > 42023 Saint-Étienne Cedex 2 > France > Tél:+33(0)4 77 42 66 03 > Fax:+33(0)4 77 42 66 66 > http://zimmer.aprilfoolsreview.com/ > -- -ericP office: +1.617.599.3509 mobile: +33.6.80.80.35.59 (eric@w3.org) Feel free to forward this message to any list for any purpose other than email address distribution. There are subtle nuances encoded in font variation and clever layout which can only be seen by printing this message on high-clay paper.
Received on Monday, 14 October 2013 18:51:50 UTC