I'm also experiencing issues and finding 502 Bad Gateway errors.
However, they aren't related to regular expressions. These issues also appear in other cases, even with the simplest queries.
https://davidabian.com/downloads/wikidata/502-error-sparql.png
El 25/09/16 a las 12:32, Ed Summers escribió:
I've been experimenting a bit with queries that contain regular expressions and have noticed that they seem to be triggering 502 Bad Gateway errors. Or perhaps it's just a coincidence and there were other things going on around 10AM GMT?
Here's an example query where I'm looking for cities that start with "Silver":
PREFIX rdfs: http://www.w3.org/2000/01/rdf-schema# PREFIX wd: http://www.wikidata.org/entity/ PREFIX wdt: http://www.wikidata.org/prop/direct/
SELECT ?s ?label WHERE { ?s wdt:P31 wd:Q515 . ?s rdfs:label ?label FILTER(regex(?label, "^Silver")) } LIMIT 15
Am I doing something wrong in the query? Occasionally it seems to work, but most of the time it waits for a while and then I get the 502 error. Any guidance you may have would be appreciated.
//Ed