On 01/09/13 16:49, Charles Li wrote:
Thanks, Andy!
I am trying to get the exact string for the "<http://example/xyz/foo>" part
in your message. However, the model I loaded into Jena from the RDF xml
doesn't have a default namespace.
Here are my findings:
When I print out with the following debug lines:
System.out.println("URI = " +
soln.get("?o").asResource().getURI());
System.out.println("Local Name = " +
soln.get("?o").asResource().getLocalName());
System.out.println("Namespace = " +
soln.get("?o").asResource().getNameSpace());
System.out.println("Class = " + soln.get("?o").asResource().getClass());
I got:
Namespace = file:///C:/temp/myrdf.xml#
Class = class
com.hp.hpl.jena.rdf.model.impl.ResourceImpl
URI =
file:///C:/temp/myrdf.xml#_{0E43691F-0B64-42AF-AFCF-19BCC28ACBA3}
Local Name =
This does not make sense - that output does not correspond to the debug
lines. The order is different. Details matter. Your doing something
but it's not clear what the data is or what exactly you have done.
And when I tried to dump the model into a TURTLE format, I got the
following error:
{E211} Base URI is null, but there are
relative URIs to resolve.: <#_{0E43691F-0B64-42AF-AFCF-19BCC28ACBA3}>
That does not look like an error from the Turtle writer. It looks like
it's from the RDF/XML reader as it's talking about "resolving".
And when I run the following SPARQL, it returned nothing:
select ?s ?p ?o where
{
?s ?p <file:///C:/temp/myrdf.xml/
_{0E43691F-0B64-42AF-AFCF-19BCC28ACBA3}> .
This will not work for several reasons.
1/ rdf:ID is not a predicate - there is no triple for ?s rdf:ID ?o.
rdf:ID will affect the subject position, not the object position.
(If you spell rdf:ID wrong, it can cause objects to be created.)
2/ It's a different URI to print out above - the # has become a /.
?s ?p ?o .
}
What did I miss?
Please provide a complete, minimal example and details of the version of
the software you're using. Descriptive fragments aren't enough for
anyone to see what exactly you are doing.
1/ "complete" means has data and code - something someone else can run
with little additional work, any of which migh obscure the issue
2/ "minimal" illustrates just the point in question and is triped down
to the least needed to show what's going on.
I suggest you include writing your data out as N-triples as well to see
what the structure is.
Andy
Thanks a lot for your kindly help!!
- Charles
On Sun, Sep 1, 2013 at 4:30 AM, Andy Seaborne <[email protected]> wrote:
On 01/09/13 01:39, Charles Li wrote:
Thanks, Rob!
What I really need to do is to query by a given rdf:ID string, since I am
building an RDF/XML traversing tool. My challenge is how to quickly get
all
triples whose subject has a given RdfID.
As you know rdf:ID is an RDF/XML artifact and there is no such a triple in
the model whose predicate is "ID". How would up come up with a SPARQL
query
to take a string of the rdf:ID input and return all triples whose subject
has the given RdfID?
Any help is greatly appreciated!!!
rdf:ID is not a predicate; it's a syntax for the subject.
If you have rdf:ID="foo"
and the base URI for the data is http://example/xyz/
then the subject is http://example/xyz/foo.
Query with
<http://example/xyz/foo> ?p ?o
Try writing your data out as N-triples to Turtle to see the structure and
the actual URIs.
Andy
- Charles
On Sat, Aug 31, 2013 at 12:16 PM, Rob Vesse <[email protected]> wrote:
There's no need to do a FILTER(?s IN sub query) and as you have found out
this is actually illegal SPARQL
You can however put the sub query in directly and get the desired effect.
SPARQL evaluation is bottom up so the inner query gets evaluated first
Rob
______________________________**__________
From: Charles Li [[email protected]]
Sent: 31 August 2013 09:36
To: [email protected]
Subject: How to filter SPARQL query with a list
Hi, all Jena/SPARQL experts!
I am composing a SPARQL query trying to list all triples whose subjects
are
in a list of RdfId's, and this list of RdfId's are from another select
query:
select ?s ?p ?o
WHERE
{
?s ?p ?o
FILTER(?s in (
select distinct ?s WHERE
{
?s ?p ?o
FILTER(contains(str(?o),
"_{000E9C27-150C-480B-9CC7-**E23FFC62C90A}"))
}
) &&
!(contains(str(?o), "_{000E9C27-150C-480B-9CC7-**
E23FFC62C90A}"))
)
}
order by ?s
However, the SPARQL query is not well-format, and it seems that it
doesn't allow another "select" in place for the list of values.
Can someone help me and advice how I can put in a list of RdfId's from
another query (lines 6 - 10)?
Thanks a lot!
- Charles
