Hi,
I noticed is that in the virtuoso conductor under RDF/Graphs a few graphs are
listed, but that this list is different from what I get with this SPARQL-query:
SELECT ?g count(*)
WHERE { GRAPH ?g {?s ?p ?o.} }
GROUP BY ?g
ORDER BY DESC 2
(As a side-note: this SPARQL-query might take a long time.)
What striked me even more is that the graphs mentioned above are different from
these:
SELECT DISTINCT ?g WHERE { GRAPH ?g {?s ?p ?o.} }
(As a side-note: this SPARQL-query returns in a split second.)
Any idea what's going on or what I'm doing wrong?
I currently think that the list I can see in the conductor is taken from this
SQL-query:
select * from SPARQL_SELECT_KNOWN_GRAPHS_T;
which actually is the view of the SPARQL_SELECT_KNOWN_GRAPHS procedure.
Nevertheless I couldn't find out why this is "out of sync" and how to get it
back to sync.
Another SQL-query:
select distinct id_to_iri(g) from rdf_quad;
(also takes quite a while) shows the list of graph IRIs corresponding to the
first SPARQL-query.
Another puzzling fact is that the renaming action in the Graphs tab actually
does not seem to rename, but clone the graph (which can again only be seen by
the above first SPARQL-query, while the Graphs Tab and the second SPARQL-query
do not show the old name anymore).
I hit all these problems after I used the Schemas tab to load the old SKOS
vocabulary: I imported this IRI in the Schemas tab:
http://www.w3.org/2004/02/skos/core/history/2006-04-18.rdf
(please tell me if this was a wrong idea... I actually don't know why there's
a distinction of Schemas and Graphs and probably did something wrong here).
Afterwards I wanted to delete the existing http://www.w3.org/2004/02/skos/core
graph in the Graphs tab and wanted to rename
http://www.w3.org/2004/02/skos/core/history/2006-04-18.rdf to
http://www.w3.org/2004/02/skos/core .
But I can't delete http://www.w3.org/2004/02/skos/core (it's in the list of
the Graphs tab, but when clicking on delete I get):
> An error has occurred when processing "/conductor/sparql_graph.vspx" page.
> SQL State 42S12
> SQL Message
>
> SR201: Primary key not found in delete.
The SPARQL query mentioned above still shows both graph IRIs:
http://www.w3.org/2004/02/skos/core
http://www.w3.org/2004/02/skos/core/history/2006-04-18.rdf
I then tried to rename the graph http://www.w3.org/2002/07/owl# to
http://www.w3.org/2002/07/owlHash. The Graphs tab now correctly excluded the
old owl# and instead shows owlHash, but when SPARQLing as above, the owl# is
there plus the owlHash.
Cheers,
Jörn
