Hello Ivan, thanks for clarifying this. A follow up question: is it a good idea to drop and re-create the DefaultQuadStorage? Will it delete any system data besides the RDF I stored myself?
Thanks, Mirko 2011/2/1 Ivan Mikhailov <[email protected]> > Hello Mirko, > > All metadata about all RDF storages are kept in "system" graph > <http://www.openlinksw.com/schemas/virtrdf#> (namespace prefix > virtrdf: ) . Subjects of type virtrdf:QuadStorage are RDF storages. > There are three of them by default: > > SQL> sparql select * from virtrdf: where { ?s a virtrdf:QuadStorage }; > s > VARCHAR > > _______________________________________________________________________________ > > http://www.openlinksw.com/schemas/virtrdf#DefaultQuadStorage > http://www.openlinksw.com/schemas/virtrdf#DefaultServiceStorage > http://www.openlinksw.com/schemas/virtrdf#SyncToQuads > > 3 Rows. -- 3 msec. > > virtrdf:DefaultQuadStorage is what's in use if no input:storage > specified. > virtrdf:DefaultServiceStorage will be used for SPARQL federation. > virtrdf:SyncToQuads is to keep the list of RDF Views that are translated > into RDB2RDF triggers. > > There are two ways of using your RDF View in SPARQL endpoint without > define input:storage. > > 1. Create RDF View right in virtrdf:DefaultQuadStorage or add the view > in other storage and then copy it from there to > virtrdf:DefaultQuadStorage . > In any of these two variants, use > SPARQL ALTER QUAD STORAGE virtrdf:DefaultQuadStorage ... > 2. Use SYS_SPARQL_HOST table as described in > http://docs.openlinksw.com/virtuoso/rdfsparql.html#rdfdefaultgraph > and set SH_DEFINES so it contains your favorite define input:storage > > Best Regards, > > Ivan Mikhailov > OpenLink Software > http://virtuoso.openlinksw.com > > On Mon, 2011-01-31 at 14:36 +0100, Mirko wrote: > > Hi, > > I have two questions on the Virtuoso quad storages: > > > > > > #1 > > I created an RDF view from relational data in Virtuoso. I did it > > manually, like demonstrated in the tutorial here > > (http://virtuoso.openlinksw.com/whitepapers/relational%20rdf%20views% > > 20mapping.html) . My RDF output are two graphs which reside in a quad > > storage named http://localhost:8890/rdfv_demo/quad_storage/default. > > > > > > I can access the RDF over the SPARQL endpoint with the following > > query: > > > > > > define input:storage > > <http://localhost:8890/rdfv_demo/quad_storage/default> > > select * where { ?s ?p ?o } > > > > > > Now, is there a way to define internally (once) that the quad storage > > should be included in queries to the SPARQL endpoint? So that the user > > does not have to define the input:storate explicitely in each query, > > like this: > > > > > > http://localhost:8890/sparql?query=select * where > > { ?s ?p ?o }&default-graph-uri=NULL&named-graph-uri=NULL > > > > > > #2 > > I think that I didn't quite get the concept of quad storages. Maybe > > that's my problem in the above question. How can I see which quad > > storages exist in the Conductor? How can I see in which quad storage a > > graph resides? And which is the default quad storage in which graphs > > are stored when I use the ttlp function for RDF insert? > > > > > > Thanks in advance, > > Mirko > > >
