- From: Andy Seaborne <andy.seaborne@talis.com>
- Date: Wed, 09 Jun 2010 13:14:07 +0100
- To: sparql Working Group <public-rdf-dawg@w3.org>
To summarise where I think we are:
1/ Use the expansions approach that Birte proposed in:
http://lists.w3.org/Archives/Public/public-rdf-dawg/2010AprJun/0293.html
2/ Define operators for zero length paths and for arbitrary length paths
(i.e. +).
2a/ zero length paths include all subjects/objects/constant terms as
possible bindings (and check this makes sense).
2b/ arbitrary length paths based on triple marking with
backtracking/unwinding. Define the operator by algorithm (of course,
you can implement anyway you want but this defines the correct answers
and cardinality).
3/ Need to compare the cardinality for arbitrary length paths and {n,m}
forms since they should agree, and if not, we need to understand why
(this is why I think the triple marking with unwinding is the way to go)
It may make sense to define {n,m} in terms of the arbitrary length paths
algorithm.
4/ Examples, examples, examples.
Andy
Received on Wednesday, 9 June 2010 12:14:49 UTC