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
