John; I think I may know what the basic issue is. TopBraid uses a
named graph architecture. The workspace is the dataset (the set of
graphs that a SPARQL query can execute against). Each graph is a
named graph, be it a file, database back-end connector, .xls or .xml
file, etc., and the name of the graph is the Base URI. For example,
if you look at the File Registry (Window > Show View > File Registry),
you will see all of the named graphs (base URIs) that TopBraid has
access to.
Now, given that TopBraid can access a number of triple store back-
ends, you end up with an architecture of named graphs that refer to
named graphs. The references are called "connectors" in TopBraid
parlance. This architecture would be the same for any named graph
application (often referred to as a triple store), such as Sesame or
TDB or whatever, that would allow a named graph to point to ("connect"
to) a repository of named graphs.
The way TopBraid addresses this indirection is to require a named
graph that points to the named graph in the back-end. I.e. the .tdb
or .sdb, etc. file created in TBS is a reference (connector) to the
TBS named graph that refers to the named graph in the back-end.
So in the end, it's not possible to access named graphs in Sesame the
same way that Sesame does. To get to a Sesame named graph, you need
to create a TBS named graph that points to the Sesame named graph.
The New wizard in Composer will guide you through this. For Sesame,
fill in the Sesame Repository Id, the Named graph, and a base URI
fields. As stated, the Base URI is the name of the graph in TBS. It
can be the same as the name you use in Sesame, but does not have to
be. When executing queries, using owl:imports, opening the file,
etc., the TBS named graph (base URI) is used to access the named graph
on the back-end.
If that doesn't help with these issues, let us know and we will follow
up accordingly.
-- Scott
On Oct 2, 5:28 pm, John Perdoni <[email protected]> wrote:
> Thaks Scott, I have gone back to version 3.6.1.v20120622-1546R which has
> cured the error. Unfortunately at present I am stuck with both .rdf
> extension files and a sesame repository so cannot try the other suggestions
> you make. With this in mind I am stil having trouble with named graphs
> (contexts in sesame terms), and I am not sure whether it is me or another
> issue. Let me explain
>
> I have a sesame repository called word on localhost:9090 , this repository
> has a named graph <http://notExample.com/otherCompany/#Data> I create an
> S2R connection with the following relevant parameters
> base URI:http://example.com/library/word
> service URLhttp://localhost:9090/openrdf-sesame/
> Sesame Repository ID word
>
> this connects fine and retrieves all triples that are not in a context
> (correct me if I am wrong but I thought that unless you specifically create
> a query that includes FROM or FROM NAMED , all triples should be returned
> ie if I use the following query within openrdf-workbench all works fine ,
> but in TBC the named graph triples are not returned
>
> SELECT *
> WHERE {?a a <http://example.com/library/word#word>}
>
> If I use from TBC or the workbench all is good
>
> INSERT {<http://example.com/library/word#word_8> rdf:type
> <http://example.com/library/word#word>}
> WHERE {}
>
> However the following only works from the workbench and NOT from TBC
>
> INSERT DATA{
> GRAPH <http://notExample.com/otherCompany/#Data> {
> <http://example.com/library/word#word_9> rdf:type
> <http://example.com/library/word#word>.}
>
> }
>
> If I try to create a s2r connection specifying the named graph I get
> nothing back at all
>
> I can only reach the conclusion that something is amiss, with either my
> logic or with TBC.
>
> Following on from this and trying to work round the problem because I dont
> really have a need to update the named graphs but just query them I thought
> I would take advantage of sesames built in sparql enpoint, but I have run
> into problems there which I will enlighten you in a post to follow
>
> Thanks again
>
> John
>
>
>
>
>
>
>
> On Sunday, 30 September 2012 13:51:56 UTC+1, John Perdoni wrote:
>
> > Hi I wonder if you could help
>
> > I have just come back to do some work on with my s2r files but something
> > has changed and I am now getting the following error when I try saving any
> > changes to s2r files (although the triple is created in the sesame
> > repository)
>
> > Save All Failed
> > org.topbraid.core.graph.concurrent.ThreadSafeGraph cannot be cast to
> > org.topbraid.sesame2.graph.RepositoryGraph
>
> > This even happens if i start with a new repository
>
> > ie create a sesame owlim-lite repository using sesame open-rdf
> > workbench,and export a file from tbc to this repository, if i add a new
> > triple via tbc and save i still get the error
>
> > Hope you can shed some lite on this
>
> > Regards
>
> > John
--
-- You received this message because you are subscribed to the Google
Group "TopBraid Suite Users", the topics of which include Enterprise Vocabulary
Network (EVN), TopBraid Composer, TopBraid Live,
TopBraid Ensemble, SPARQLMotion, SPARQL Web Pages and SPIN.
To post to this group, send email to
[email protected]
To unsubscribe from this group, send email to
[email protected]
For more options, visit this group at
http://groups.google.com/group/topbraid-users?hl=en
