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Questions tagged [virtuoso]

Virtuoso is a multi-model relational database management system for data represented as Relational Tables and/or RDF Property Graphs. It is also equipped with in-built middleware for conceptual data integration across heterogeneously shaped and disparately located data.

Virtuoso, (a/k/a OpenLink Virtuoso and the Virtuoso Universal Server) from OpenLink Software, is a high-performance and scalable native relational database management system (RDBMS) for data (relations) organized as tables and/or property graphs. In addition to its RDBMS functionality, it is also equipped with a middleware layer that enables conceptual data integration and web services deployment.

Virtuoso is the RDF DBMS behind live services such as DBpedia, Uniprot, Bio2RDF, the Linked Open Data Cloud Cache, and many other bubbles in the Linked Open Data Cloud.

Product-specific questions are often best raised to product-specific arenas. For Virtuoso, these include the OpenLink Community Forum, the Virtuoso Users mailing list, Open Source Edition GitHub-hosted project bug reports and other issues, confidential Support cases, etc.

Related tags :

488 questions
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How to skip bad dates in DBpedia SPARQL request?

I need to get data about films from DBpedia. I use SPARQL query as follows on http://dbpedia-live.openlinksw.com/sparql: PREFIX rdfs: PREFIX rdf: PREFIX foaf:…
Dennis Ivanoff
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Any alternatives to Virtuoso as a graph store?

I like it (very much) that is supports SPARQL/Update and the SPARQL endpoint that comes with it, but I'm a little worried about vendor lock in I think it is overkill for my requirements (I want a graph store with half a billion triples) I would…
Ashkan Kh. Nazary
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Default login credentials for Virtuoso Conductor

I've just finished installing Virtuoso's opensource package and I'm running the web gui called Conductor. It requires a login, but I don't think there was anything about setting that up during install. is there a default un / pass for this? if now,…
Kristian
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Update RDF in Triplestore

I'm experimenting with Sesame and Virtuoso Triplestores. At the Moment I use the Sesame Java API to add RDF Data to both Triplestores. My RDF Data represents different things like Videodata, Userdata etc. At the moment I can add a RDF of a Video…
mjspier
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Alternative for OPTIONAL Keyword in SPARQL-Queries?

I have a sparql-Query, that asks for certain properties of URIs of a given type. As I am not sure, whether those properties exists, I use the OPTIONAL Keyword: PREFIX mbo: PREFIX rdfs:…
Aaginor
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Sparql Query Results without Namespace

I want to get results from sparql query and the results contain no namespace. ex: there is result in triple format like: "http://www.xyz.com#Raxit" "http://www.w3.org/1999/02/22-rdf-syntax-ns#type" "http://www.xyz.com#Name" So i want to get only…
Raxit
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simple sparql query from dbpedia

I have a question about a SPARQL query that I'm trying to build from a tutorial. I want to generate triples that return a list of band members and the bands that they are in using a DBPedia endpoint. my query PREFIX dbo:…
Sara Lafia
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loading rdf triples into virtuoso opensource

I'm trying to create a local mirror of LinkedGeoData.org from this dump. That's around 61,000,000 triples. Virtuoso is supposed to easily handle a lot more than that, but every single time it stops loading after around 40,000,000 triples. I'm using…
ailnlv
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SPARQL Query with colon in predicate

I am trying to query the RDF Data from linkedgeodata.org for States within a Country. In RDF it is represented as such: "LT" . As you might…
Markus
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Adding triples to Virtuoso triplestore with Python and RDFLib

I need to make a program to add triples to a Virtuoso triplestore, I'm using Python and RDFLib. I've installed the Virtuoso plugin and tried a connection as seen in http://pythonhosted.org/virtuoso/rdflib.html#virtuoso-storage. I got: from…
FontFranch
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Neo4j vs OpenLink Virtuoso

I've been using OpenLink Virtuoso as an RDF store for some time now and although it's great with large data, I'm not satisfied with the graph traversal performance using SPARQL. Recently I've heard a lot about Neo4j's traversal performance and…
parsa
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Why are escaped characters not allowed in SPARQL queries when using PREFIXes?

The following query throws Virtuoso 37000 Error SP030: SPARQL compiler, line 0: Bad character '%' (0x25) in SPARQL expression at '%' PREFIX res: PREFIX yago: SELECT * WHERE { …
ThomasH
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How do I iterate over a SPARQL query referring to a virtual graph?

I am developing a Virtuoso stored procedure. I want to perform a loop over the result of a SPARQL query to a graph. The problem comes when the query contains a reference to a virtual graph (a graph not physically in the triplestore, being the…
Bepi
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Virtuoso ISQL data import can't stat file

In isql-vt (the Ubuntu name for Virtuoso's isql), I am trying to import a test .ttl file, but get the error "Can't stat file": SQL> DB.DBA.TTLP(file_to_string_output('./scratch/ttl/granule.ttl'),'','http://origin.mytest.org/'); *** Error 42000:…
Randall
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How to access Virtuoso RDF store from Python?

I would like to access Virtuoso RDF store from Python much like I do Postgres using psycopg. After some googling, I came to the this page but I couldn't get either SQLAlchemy sqlalchemy.exc.NoSuchModuleError: Can't load plugin:…
amphibient
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