- From: Andy Seaborne <andy.seaborne@talis.com>
- Date: Thu, 03 Jun 2010 12:38:31 +0100
- To: Birte Glimm <birte.glimm@comlab.ox.ac.uk>
- CC: SPARQL Working Group <public-rdf-dawg@w3.org>
On 03/06/2010 12:20, Birte Glimm wrote: >>>> :a :p :b . >>>> >>> :b :p :z . >>>> >>> :a :p :c . >>>> >>> :c :p :z . >>>> >>> :c :p :c . >>>> >>> >>>> >>> Pattern: { :a :p+ ?z } >>>> >>> ?z=:b >>>> >>> ?z=:c >>>> >>> ?z=:z >>> >> >>> >> with edge marking: >>> >> b, c, c, z, z > disagree: b, c, z, z, z > c is always just once, but z occurs three times with edge marking no > unwind, and four times with unwind. Without unwind it tells you > something about the graph, i.e., there are three edges going to :z. > Unwinding makes you go round the loop twice, once for each way you > reached :z. :a :p :b . :b :p :z . :a :p :c . :c :p :z . :c :p :c There are two edges into :z, from :b and :c and there are two edges into :c, from :a and :b which is how I got 2 c's and 2 z's. Andy
Received on Thursday, 3 June 2010 11:39:08 UTC