Thank You so much gentlemen! 

I will make the suggested modifications and hopefully I will make that work. 

Have a great day! 
Best Regards


Hyrundo

> On Nov 28, 2019, at 11:33 AM, Andy Seaborne <[email protected]> wrote:
> 
> Hi Hyrundo,
> 
> The query as written is executed locally, and when execution reaches the 
> SERVICE clauses the engine calls out to the named service.
> 
> Instead of:
>  QueryExecutionFactory.sparqlService
> use
>  QueryExecutionFactory.create
> 
>    Andy
> 
> On 27/11/2019 16:23, Hyrundo Publishing Association wrote:
>> Hello Sirs at Jena,
>> I am following the examples of federated queries given at this URL:
>> https://www.oclc.org/developer/news/2016/federated-queries-with-sparql.en.html
>>  
>> <https://www.oclc.org/developer/news/2016/federated-queries-with-sparql.en.html><https://www.oclc.org/developer/news/2016/federated-queries-with-sparql.en.html
>>  
>> <https://www.oclc.org/developer/news/2016/federated-queries-with-sparql.en.html>>
>> and then I’m trying to replicate the results bringing those SPARQL examples 
>> into a Jena/Java Main class in NetBeans…
>> with no results…
>> For example, the given SPARQL code:
>> PREFIX schema: <http://schema.org/>
>> PREFIX library: <http://purl.org/library/>
>> PREFIX wdt: <http://www.wikidata.org/prop/direct/>
>> PREFIX dct: <http://purl.org/dc/terms/>
>>  SELECT ?work ?workLabel
>> FROM <http://www.worldcat.org/oclc/470488115>
>> WHERE {
>> <http://www.worldcat.org/oclc/470488115> schema:author ?creatorURI.
>> BIND(replace(STR(?creatorURI), "^(.*[\\/])*", "") AS ?creatorID)
>>  {SERVICE <https://query.wikidata.org/sparql> { //endpoint n.1
>>      ?author wdt:P214 ?creatorID.
>>      ?work wdt:P50 ?author .
>>   ?  work wdt:P1476 ?workLabel
>>   }
>> }
>> UNION
>> {
>> SERVICE <http://bnb.data.bl.uk/sparql> { //endpoint n.2
>>      ?bl_creator  ?creatorURI.
>>      ?work dct:creator ?bl_creator.
>>      ?work dct:title ?workLabel
>>      }
>>   }
>> }
>> When having two different endpoints to query, how to set the query execution 
>> in Jena?
>> Query query = QueryFactory.create(queryStr);
>> QueryExecution qexec = 
>> QueryExecutionFactory.sparqlService(“http://URL_of_the_SPARQL_endpoint 
>> <http://url_of_the_sparql_endpoint/>", query)   ?
>> Any hint?
>> Thank you in advance.
>> Hyrundo

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