Questions tagged [blazegraph]

Blazegraph is an open-source RDF/graph database capable of clustered deployment. This tag is specific for questions on the database API. RDF and SPARQL are often related technologies.

Overview

Blazegraph is an open-source, ultra-scalable, high-performance graph database written in Java. It supports various technologies such as:

Blazegraph offers different operating modes (triples, provenance, and quads) and either operates as an embedded database or over a client/server REST API.

Blazegraph supports up to 50 billion edges on a single machine and has a high availability and scale-out architecture. It is in production use for Fortune 500 customers such as EMC, Autodesk, and many others. It was selected by the Wikimedia foundation to power their Wikidata query service.

Documentation links

The official Blazegraph website can be found here. In-depth technical details on the graph database can be found in the official Blazegraph Wiki. The Blazegraph API itself is documented on GitHub.

Background information on the big-data architecture, internals, and deployment models can be found in several white papers in the Blazegraph Blog.

When to use this tag

Please use the tag on questions about the database API. If you have a more general question to which an answer might not necessarily depend on the Blazegraph API, please consider including or .

If you want to discuss or suggest Blazegraph features, please do it via the Blazegraph contact page.

Related tags

Adapted from the Blazegraph website and the Blazegraph Wiki.

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Using Blazegraph's `NanoSparqlServer`, how to clear the graph between tests?

I am using Blazegraph's 1.5.3 version of their Bigdata DB (now rebranded as Blazegraph). I have a service that acts as a Gateway, implementing a bunch of persistence-layer methods. Now I'm writing unit tests for those methods. I'm using the embedded…
Mack
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How can I export all results from Blazegraph into a file?

I would like to export the results of my SPARQL query from Blazegraph into a file. However, it exports only the first page of the results. When I try to display all results, my browser crashes. How can I fix this? I'm running Blazegraph 2.1.2 on a…
Fabian_G
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Why is owl:Restriction inference not working in Blazegraph

I'm trying to follow the example given in this answer on OWL reasoning in Blazegraph, but the query: select * where { :John rdf:type ?type } returns only: type: owl:NamedIndividual, owl:Thing but not the expected inference: type:…
igor.br
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Blazegraph Tinkerpop 3 Indexing

I am trying to learn about Blazegraph. At the moment I am puzzled how I can optimise simple lookups. Suppose all my vertices have a property id, which is unique. This property is set by the user. Is there any way to speed up finding a vertex of a…
Filipe Teixeira
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Which graph database is suitable for a social media project?

I want to start a project based on a graph database. We are struggling with selecting a database. Our project is about social media sharing (more than media). Each user has a profile like on Facebook with some properties (city, friendship, following…
Yuseferi
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How can I make Blazegraph and SWRL work together?

I have written an SWRL rule in an ontology I've written. Specifically, the rule is: hasSampleLocale(?i, tag_retail) -> hasSampleLocale(?i, tag_domestic) This works just fine and dandy when I test it in Protege with the Hermit reasoner, but alas it…
sam_peels
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Docker container with Blazegraph Triple Store not working possibly due to networking

I'm preparing a Docker image to teach my students the basics of Linked Data. I want them to actually prepare proper RDF and simulate the process of publishing it on the web as Linked Data, so I have prepared a Docker image comprising: Triple Store:…
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Sesame/Jena SPARQL results to JSON-LD

I've seen the answer on How to return SPARQL results in JSON-LD?, but it's not satisfying/working. I used the JSON-LD Java Integration for Sesame, as well as the standalone version. What I want to achieve: Send a SPARQL CONSTRUCT query to a SPARQL…
mchlfchr
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How can I access an ontology from RDFLib?

How can I connect to a triple store and access an ontology through the RDFLib Python API? The triple store I am using is Blazegraph. I know how to access Virtuso, but about Blazegraph I am not sure.
Niharika Roy
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Why is owl:Restriction reasoning not working in Blazegraph?

With the following RDF in Blazegraph (taken from this answer): :eats rdf:type owl:ObjectProperty . :Vegetable rdf:type owl:Class ; rdfs:subClassOf owl:Thing . :Vegetarian rdf:type owl:Class ; owl:equivalentClass [ rdf:type…
kaychaks
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BigData Vs Neo4J

I´ve been looking for a triple store for my project. In this project i want to store my data according to certain ontologies (OWL). From my research i ended up with two tecnologies Neo4J and BigData that seems to fit well in this case. I want to…
rtcardoso
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Error: java.util.concurrent.ExecutionException: java.lang.IllegalStateException: Unknown transaction in Blazegraph

I am running below SPARQL query to delete some triples from blazegraph (from UPDATE tab). DELETE { graph { ?s ?b ?c } } where { graph { ?s ?b ?c FILTER (strstarts(str(?s),…
rshar
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Error while deleting triples from a graph in Blazegraph

I am beginner in SPARQL and in my current task I have to delete some triples where the subject matches a specific string. I am running this delete query on a graph in Blazegraph. This is my query: prefix skos:…
rshar
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QueryBadFormed: QueryBadFormed: SPARQLWrapper

I am trying to insert triples into blazegraph using below sparql query. for index, row in df_omim.iterrows(): omim = row['mim_number'] omim_label = row['preferred_title_symbol'] rel = row['skos_rel'] meddra = row['MDR_code'] …
rshar
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Blazegraph import large files

I using dockerized version of Blazegraph (https://hub.docker.com/r/nawer/blazegraph) and I am trying to import a large file to Blazegraph. It gave me a warning "File too large, enter the path to file" with an example (/path/to/Thesaurus.owl). So I…
Erwarth
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