Thanks Andy!
I managed to narrow down to the following SPAQL query issue (the model was
in TDB loaded from file "C:/temp/myrdf.xml". Jena 2.10.1)
When I run the following query:
select ?s ?p ?o
WHERE
{
<file:///C:/temp/myrdf.xml#ROOT> ?p ?o .
}
I was able to get the correct triples (the logical tree structure root is
modeled in the RDF file with a node whose RdfId is literally "ROOT") .
However, when I plug in the RdfId with the following query:
select ?s ?p ?o
WHERE
{
<file:///C:/temp/myrdf.xml#
_{27900499-0D9D-4287-8F4D-E4C13BCB3C8D}> ?p ?o .
}
I got an error:
Encountered " "<" "< "" ......
So I think it may be due to the special characters in the RdfID, and I
tried the following query:
select ?s ?p ?o
WHERE
{
URI(ENCODE_FOR_URI("file:///C:/temp/myrdf.xml#_{27900499-0D9D-4287-8F4D-E4C13BCB3C8D}"))
?p ?o .
}
But still syntax error.
How should I compose the SPARQL query string to specify the RdfID in
place correctly?
Thanks a lot!
- Charles
On Sun, Sep 1, 2013 at 12:21 PM, Andy Seaborne <[email protected]> wrote:
> 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
>>>>>
>>>>>
>>>>>
>>>>
>>>
>>
>
