Re: Remote named graph

[Andy Seaborne]

On 28/08/12 23:19, Frank Lee wrote:
Hi, Andy.
Thanks so much for your warm help.

Obtaining the handle of  DatasetAccessor what I really wanted. Thanks.

BTW, how can we get the list/interator of namedGraphs from DatasetAccessor or 
ARQ?

You can use:

SELECT ?g { GRAPH ?g {} }

the interface DatasetAccessor does not provide such an operation and you 
need to get it from elsewhere - the interface could be used to a thing 
that stores graphs as a distributed map without ability to enumerate all 
keys ... like a very large key-value store providing just the SPARQL 
Graph Store Protocol (which despite the name, is not a query protocol).

        Andy


Thanks.
Frank



________________________________
  From: Andy Seaborne <a...@apache.org>
To: users@jena.apache.org
Sent: Tuesday, August 28, 2012 2:05 AM
Subject: Remote named graph

Hi, Andy,

It's easy to get the model for a named graph from local TDB dataset

tdb_dir = "c:\\tdb";

ds = TDBFactory.createDataset(tdb_dir);


String ngUri = "http://xxx .."
Model model = ds.getNamedModel(ngUri);

However, if we run fuseki server with TDB remotely,  how can we get the model 
for the specified named graph?
For instance, the fuseki server run at remote server with IP address: 
172.25.19.233 and tdb directory is /home/tdb at linux machine.

Thanks.

Frank


+++

Frank,

I'm not sure what you mean: access the remote named graph or pull its
contents to the local machine.

1/ Access:

Use GRAPH in a SPARQL query.

2/ The remote graph has a name using the SPARQL Graph store protocol:

http://host/datasets/data?graph=http://xxx ..

You can simple GET this although there is some code to present that
nicely in Fuseki (DatasetAccessor).

This is a local copy.

(this code will move from Fuseki into ARQ sometime with a consequent
package renaming)

     Andy