[Nepomuk] SPARQL construct queries in Soprano with Virtuoso

[Ilkka Laukkanen]

On Thu, May 6, 2010 at 7:03 PM, Sebastian Trüg <trueg at kde.org> wrote:
> I tried the query here and I got a graph. Could you monitor stderr for
> error messages, please?

I'll document exactly what I did here for reference:

Terminal 1:

$ sopranod --backend virtuoso --storagedir /var/tmp/soprano # there's
a db there that has a bunch of stuff
Using Virtuoso Version: "6.1.1.3127-pthreads"
Listening on port  5000
void Soprano::VirtuosoController::writeConfigFile(const QString&,
const Soprano::BackendSettings&) "/tmp/virtuoso_TJ8638.ini"
Starting Virtuoso server: "/usr/local/bin/virtuoso-t" ("+foreground",
"+configfile", "/tmp/virtuoso_TJ8638.ini", "+wait")
(...the rest of the virtuoso messages...)
Virtuoso started: 8646
Soprano::ODBC::Connection::Connection()
Soprano::Server::DBusController(0x25e3d80)
virtual Soprano::ODBC::Connection::~Connection()
Soprano::Server::DBusController(0x25e3d80)
Soprano::ODBC::Connection::Connection()
Soprano::Server::DBusController(0x25e3d80)
Connecting to deprecated signal
QDBusConnectionInterface::serviceOwnerChanged(QString,QString,QString)

Terminal 2:

$ sopranocmd --dbus org.soprano.Server --model main query "$(cat
myquery.sparql)" # myquery as documented in earlier email
fmtaggret- -> "@prefix rdfs:\t<http ....etc

The result is the same as it was through the API. I'm not sure what a
graph query result through sopranocmd should look like though?
Probably not like that?

Poking around, I also tried

$ sopranocmd --dbus org.soprano.Server --model main --serialization
rdfxml query "$(cat myquery.sparql)"
Can only serialize graph queries

That error message is very interesting. How is my construct query not
a graph query?


-- 
Ilkka