我正在尝试执行从 Nobelprize 端点到 wikidata 端点的 SPARQL 联合查询,但它返回一个
502 Proxy Error
。
代码:
select * where { SERVICE <https://query.wikidata.org/sparql> { ?j ?k ?l } } LIMIT 10
我尝试过的事情:
SPARQL-QUERY: queryStr=select * where { SERVICE <https://data.nobelprize.org/store/sparql/> { ?j ?k ?l } } LIMIT 10
查询dbpedia并运行:
SELECT * WHERE { SERVICE <http://dbpedia.org/sparql>{ SELECT * WHERE{ ?s ?p ?o } LIMIT 10 }
}`
查询europeana和works:
SELECT * WHERE { SERVICE <http://sparql.europeana.eu/>{ SELECT * WHERE{ ?s ?p ?o } LIMIT 10 } }
感谢 UninformedUser 的回答,我可以解决问题:
download the Nobel Prize Dataset dump from here, load into Fuseki, then do an efficient federated query which does select some data from the local dataset and enrich it with Wikidata via SERVICE clause
P.S.:我必须从https://www.ida.liu.se/research/semanticweb/events/SemWebCourse2018/nobelprize.nt下载数据集,但效果很好