virtuoso

问题 I have Virtuoso 7.10 and command VALUES works for 1*x or x*1 asign to tables like: SELECT * WHERE { VALUES (?z ?r ?t) { ("x" "y" "z") } } and for: SELECT * WHERE { VALUES ?z { "x" "y" "z" } } But the problem is when i try to assign like this: SELECT * WHERE { VALUES (?z ?r ?t) { ("x" "y" "z") ("xy" "yx" "zx") } } then in result, i have only first column filled, but other two are empty (same as with two column). Is it a bug or am I doing something wrong? Is there a workaround? 来源： https:/

问题 I have Virtuoso 7.10 and command VALUES works for 1*x or x*1 asign to tables like: SELECT * WHERE { VALUES (?z ?r ?t) { ("x" "y" "z") } } and for: SELECT * WHERE { VALUES ?z { "x" "y" "z" } } But the problem is when i try to assign like this: SELECT * WHERE { VALUES (?z ?r ?t) { ("x" "y" "z") ("xy" "yx" "zx") } } then in result, i have only first column filled, but other two are empty (same as with two column). Is it a bug or am I doing something wrong? Is there a workaround? 来源： https:/

问题 I was going through this link, which uses EXPLAIN() to show us the SQL query that Virtuoso generates(uses internally) for the input SPARQL query. I tried it on my Virtuoso 7.x version and found that I get a different output. I am not able to understand the output fully. Would it be possible to explain what this output from iSQL means and how I would interpret a SQL query from this? The SPARQL query is SPARQL SELECT DISTINCT ?s FROM <http://dbpedia.org> WHERE { ?s a <http://dbpedia.org

问题 I have a SPARQL query which returns the most specific common classes of two resources. When I try to run it on https://dbpedia.org/sparql, sometimes it returns nothing, and other times it returns the classes I want. I have noticed it is related to the order of the statements in the query. This is not a desirable behavior because, when I execute the query, I expect it to have the same results regardless of the order in which I input the URIs of the resources. Has anyone experienced this

问题 I wrote a query in DBpedia SPARQL: select distinct ?s where { ?s rdf:type dbo:Writer. ?s rdf:type yago:LivingPeople. ?s dbo:birthDate ?year. FILTER (?year > 1964-01-01). } but it is showing: Virtuoso 42000 Error The estimated execution time 82850 (sec) exceeds the limit of 240 (sec). What is the problem? How can I solve this? 回答1: The error message tells you the problem -- processing the query is expected to take 82850 seconds, but the server is set to only run for 240 seconds. You can solve

问题 I have problem with SPARQL. I want to select something from category. For example subjects. I make query like this in http://dbpedia.org/snorql. SELECT ?category ?subject WHERE { ?category a skos:Concept . ?category skos:Concept: American_punk_rock_guitarists. ?category dct:subject ?subject . } LIMIT 1000 I have error Virtuoso 37000. I don't understand why. P.S. Is it good book for beginnier in SPARQL - Learning SPARQL, 2nd Edition Querying and Updating with SPARQL 1.1 ? 回答1: You have at

问题 I am using two different HTTP POST utilities (poster out of Firefox as well as Python requests API) to post a simple SPARQL insert to Virtuoso . My URL is: http://localhost:8890/sparql My request parameters are: default-graph-uri: <MY_GRAPH> should-sponge: soft debug: on timeout: format: application/xml save: display fname: I put the actual SPARQL ( INSERT DATA { GRAPH... ) in the content of the message. I tried different content types, none of which worked. I do get 200 but the response is

问题 I am trying to single upload an .rdf file to virtuoso with the ld_dir command, as follows: ld_dir('/home', 'filename.rdf', 'http://domain.example/TEST'); The operation seems to be done, although it takes 1 msec; which is not logical.. however when I try to view the content of the grapgh using: SELECT * FROM <http://domain.example/TEST> WHERE {?p ?o ?s} it just does not display any results. Performing the same query on another graph brings out results. 回答1: ld_dir command will only bring RDF

问题 As we write SPARQL in Virtuoso, it is easy to escape a space within an URI by coding the space with %20 . However, when I run the same query on Virtuoso isql service, the escape fails. Here is my query: PREFIX wd: <http://www.wikidata.org/entity/> PREFIX wdt: <http://www.wikidata.org/prop/direct/> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> PREFIX wdno: <http://www.wikidata.org/prop/novalue/> PREFIX schema: <http://schema.org/> PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#

问题 I get the following error. Virtuoso 22007 Error DT006: Cannot convert -0359 to datetime : Incorrect month field length SPARQL query: define sql:big-data-const 0 #output-format:text/html define sql:signal-void-variables 1 select ?item bif:year(xsd:dateTime( str(?dob))) as ?m{ ?item <h://f.cm/ns/common/topic/notable_types> <h://f.cm/ns/people/person> . ?item <h://f.cm/ns/people/person/date_of_birth> ?dob } limit 675 If I change the limit to 674 , it works. What I suspected was that some