Menu
▾
▴
Re: [dotNetRDF-Develop] Stackoverflow calling QueryWithResultGraph()
|
From: Rob N. <ro...@co...> - 2014-01-30 18:27:01
|
dotnetRDF library to query (via .NET4.5 build) Jena Fuseki for the Triple Store and Endpoint (I forget specific versions, but will check if helpful) mmx is our Dataset Calling code is basically (omitted the noise): _endpoint = new SparqlRemoteEndpoint(http://jena:3030/mmx/query); IGraph graph = _endpoint.QueryWithResultGraph(thequery); // ß Stackoverflow here Where thequery is: 1 PREFIX dc: <http://purl.org/dc/elements/1.1/> 2 PREFIX exif: <http://www.w3.org/2003/12/exif/ns/> 3 PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> 4 PREFIX mmx: <http://data.sciencemuseum.org.uk/def/ontology/> 5 PREFIX foaf: <http://xmlns.com/foaf/0.1/> 6 PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> 7 PREFIX skos: <http://www.w3.org/2004/02/skos/core#> 8 PREFIX dcterms: <http://purl.org/dc/terms/> 9 10 CONSTRUCT 11 { ?ass mmx:relatedArchiveDocument <http://id.sciencemuseum.org.uk/archivedocument/smad-110001337> . 12 ?ass rdf:type mmx:Asset . 13 ?ass dcterms:hasVersion ?ver . 14 ?ver ?pred2 ?obj2 . 15 ?ass ?p2 ?o2 .} 16 WHERE 17 { { GRAPH ?g 18 { ?ass mmx:relatedArchiveDocument <http://id.sciencemuseum.org.uk/archivedocument/smad-110001337> . 19 ?ass dcterms:hasVersion ?ver . 20 ?ver ?pred2 ?obj2 21 } 22 } 23 UNION 24 { GRAPH ?g 25 { ?ass mmx:relatedArchiveDocument <http://id.sciencemuseum.org.uk/archivedocument/smad-110001337> . 26 ?ass ?p2 ?o2 27 } 28 } 29 } Thought Id exclude the setup and query as, as mentioned, the query does work (and did, only recently started throwing the exception hence I wondered if it was data, or maybe encoding, related based on how dotnetRDF is parsing ). The attached triples were the result of the construct from above, not the entire triple store. This all works fine for small result sets, its just this particular query returns 360 relatedArchiveDocuments and the library doesnt seem to like it. If its nothing obvious, I will grab your source code and try and debug further cant tell much of what is happening within QueryWithResultGraph() atm. /Rob From: Rob Vesse [mailto:rv...@do...] Sent: 30 January 2014 17:12 To: dotNetRDF Developer Discussion and Feature Request Cc: ro...@co... Subject: Re: [dotNetRDF-Develop] Stackoverflow calling QueryWithResultGraph() Rob You didn't include the query or any context of how you invoke the query so we can't really offer any attempt at diagnosis. Please provide a minimal complete example. Are the results you provided the results of a successful run of the specific query or a dump of the entire test dataset? Nothing looks untoward with the data so likely some interaction with the specific query. QueryWithResultGraph() implies use of SparqlRemoteEndpoint (whether directly/indirectly) to query a remote service so can you provide the code that invokes the query plus the specific problematic query. The only kind of query that springs to mind that could easily lead to a StackOverflow would be a complex property path but without seeing the query I can't tell, it may well be something innocuous hitting a rare corner case in our SPARQL engine. Also what can you tell us about the set up of that remote service since you imply you control that as well. Is the remote server using dotNetRDF to host the data, if so what's the setup? Or if it isn't under your control can you tell us anything about it e.g. endpoint, server software if known etc Thanks, Rob Vesse From: Rob Nicholls <ro...@co...> Reply-To: dotNetRDF Developer Discussion and Feature Request <dot...@li...> Date: Thursday, 30 January 2014 05:44 To: <dot...@li...> Subject: [dotNetRDF-Develop] Stackoverflow calling QueryWithResultGraph() Hi all, Im receiving consistent stack overflows from QueryWithResultGraph(query) when using a specific query against our triple store. The query runs fine (within ms) and returns results ok. Results returned from the triple store are in the attached file (queryresults.txt), not a huge amount of data to justify killing a 12GB web server, and it does occasionally function correctly on my developer machine (never when running the debugger though). Can anyone offer any advice? Is this perhaps an issue with the data itself causing some kind of circular reference? Although doesnt explain why it occasionally works. Using: dotnetRdf 1.0.3 / .NET4.5 Many thanks, Rob cogapp Rob Nicholls Senior Programmer +44 1273 821600 <http://www.cogapp.com/> www.cogapp.com Cogapp Brighton 21-33 Dyke Road, Brighton, BN1 3FE. UK Cogapp New York 641 Lexington Avenue, 15th Floor, New York, NY 10022, USA News Pocahontas' portrait and letters from George Washington online: a responsive website for the <http://www.vahistorical.org/> Virginia Historical Society, just launched. For regular Cogapp news, please follow us on <https://twitter.com/cogapp> Twitter. ---------------------------------------------------------------------------- -- WatchGuard Dimension instantly turns raw network data into actionable security intelligence. It gives you real-time visual feedback on key security issues and trends. Skip the complicated setup - simply import a virtual appliance and go from zero to informed in seconds. http://pubads.g.doubleclick.net/gampad/clk?id=123612991 <http://pubads.g.doubleclick.net/gampad/clk?id=123612991&iu=/4140/ostg.clktr k_______________________________________________> &iu=/4140/ostg.clktrk_______________________________________________ dotNetRDF-develop mailing list dot...@li... https://lists.sourceforge.net/lists/listinfo/dotnetrdf-develop |
