Use SPARQL property path on DBpedia -

i'd find out if property paths exist between 2 entities on dbpedia. sample query tried on snorql:

select * { :braveheart (:|!:)* :mel_gibson } limit 100 

the queries runs memory error:

virtuoso 42000 error tn...: exceeded 1000000000 bytes in transitive temp memory. use t_distinct, t_max or more t_max_memory options limit search or increase pool sparql query: define sql:big-data-const 0 #output-format:application/sparql-results+json define input:default-graph-uri prefix owl: prefix xsd: prefix rdfs: prefix rdf: prefix foaf: prefix dc: prefix : prefix dbpedia2: prefix dbpedia: prefix skos: select * { :braveheart (:|!:)* :mel_gibson } limit 100 

i suspect someone's going suggest setting local dbpedia mirror. if that's case, i'd love detailed steps on how so.

i think query bit wrong you're trying answer... there no variables in select * can't project out (i'd consider bug compile this), let me rephrase query to

ask { dbr:braveheart (<>|!<>)+ dbr:mel_gibson } 

sadly query errs same problem described.

while agree, complicated should executed against local endpoints, above query isn't complicated @ all, considering there several direct edges between 2 nodes:

select * { dbr:braveheart ?p dbr:mel_gibson } 

i consider bug in virtuoso's query planner , reported it: https://github.com/openlink/virtuoso-opensource/issues/641

having said that, i'd point out in real cases you're interested in paths don't point forward. direction of edges depends on modelling. consider using queries these instead:

ask { dbr:braveheart ((<>|!<>)|^(<>|!<>))+ dbr:mel_gibson } 

the expression says follow edge in direction or against (^) @ least 1 step. (yes, wonder why property paths didn't short syntax arbitrary edges ;) )