- From: Alex Hall <alexhall@revelytix.com>
- Date: Fri, 14 Oct 2011 11:37:13 -0400
- To: Ian Davis <ian.davis@talis.com>
- Cc: RDF WG <public-rdf-wg@w3.org>
- Message-ID: <CAFq2bizUrN3H__UFAFo4Bt5FZM+EHebRwLesmoOxr9NnLgyL+g@mail.gmail.com>
On Fri, Oct 14, 2011 at 5:45 AM, Ian Davis <ian.davis@talis.com> wrote: > Example Document 3 in the TriG spec[1] shows the same blank node label > being used in different graphs. My interpretation of the example is that > those blank nodes are distinct, i.e. the scope of blank node labels is the > graph not the TriG document. How do the main graph stores behave? Is it > possible to put the same blank node into two different graphs? If so, this > information would not be serializable in TriG if my interpretation is > correct. > FWIW, Mulgara also allows graphs to contain blank nodes from other graphs in the case where you update one graph with statements computed from a query against another graph (inference graphs are one example). For a while we thought this was a bug; I would love to be told it's not since it's a useful thing to have. Question for the SPARQL folks: given the following sequence of operations: INSERT DATA { GRAPH <g1> { _:s <p> <o> } } INSERT { GRAPH <g2> { ?s <p> <o> } } WHERE { GRAPH <g2> { ?s <p> <o> } } Does SPARQL take any position on whether the blank node inserted into g2 is the same as or different from the one from g1? -Alex > > > > > [1] http://www4.wiwiss.fu-berlin.de/bizer/trig/ > > -- > Ian Davis, Chief Technology Officer, Talis Group Ltd. > http://www.talis.com/ | Registered in England and Wales as 5382297 >
Received on Friday, 14 October 2011 15:37:53 UTC