Returning the relationships between a given set of items - Wikidata

8 Apr 2016


      I'm using the following Neo4j Cypher query that I'd like to replace with
a SPARQL query against Wikidata:
MATCH (a:Item), (b:Item)
    WHERE a.itemId IN ['Q2', 'Q405', 'Q525'] AND b.itemId IN ['Q2',
    'Q405', 'Q525']
    WITH a, b
    OPTIONAL MATCH (a)-[rel]-(b)
    RETURN a, b, collect(rel)
The objective is to return the relationships between a given set of
items.  Here's the SPARQL query that I'm trying, but it times out:
PREFIX rdfs: http://www.w3.org/2000/01/rdf-schema#
      PREFIX wikibase: http://wikiba.se/ontology#
      PREFIX entity: http://www.wikidata.org/entity/
      PREFIX p: http://www.wikidata.org/prop/direct/
      SELECT ?subjectUrl ?subjectLabel ?propUrl ?propLabel ?objectUrl
      ?objectLabel 
      WHERE {
          hint:Query hint:optimizer 'None' .
          ?subjectUrl ?propUrl ?objectUrl .
          ?subjectUrl rdfs:label ?subjectLabel .
          ?objectUrl rdfs:label ?objectLabel .
FILTER (LANG(?subjectLabel) = 'en') .
          FILTER (LANG(?objectLabel) = 'en') .
?property ?ref ?propUrl .
          ?property a wikibase:Property .
          ?property rdfs:label ?propLabel
FILTER (lang(?propLabel) = 'en' ) .
          FILTER (?subjectUrl IN (entity:Q2, entity:Q405, entity:Q525))
          .
          FILTER (?objectUrl IN (entity:Q2, entity:Q405, entity:Q525)) .
}
      LIMIT 200
Is it feasible have a SPARQL query with this objective return in a few
seconds?  If so, can you please give me some guidance on an approach?
Thanks,
James Weaver