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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How to insert special characters like &, () and others in Sparql using python?

I am using this query to insert data: prefix : INSERT DATA { :some&Data a :ABC . } But it is failing because of the &. How can I insert the data into Blazegraph db with special characters? The same query like…
Ian Kurtis
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Blazegraph - Full text search analyzer configuration

I'm using Blazegraph 2.1.5 and I'd like to perform full text search using http://www.bigdata.com/rdf/search# service. The namespace configuration…
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Is it possible to perform an INSERT operation with the GROUP BY clause in SPARQL/Update?

Suppose I have a graph containing students from three different grades. Sample graph: rdf:type
10J01
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Local Wikidata Instance contains data but returns no results

I've been working extensively with Wikidata for about a year now and have installed a local Wikidata instance a handful of times as per the directions found in the official mediaWiki article on Wikidata. I decided to install an instance afresh just…
jecummin
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Blazegraph Data Loader

I try to import some triple into the Blazegraph data base, whereas all triple w/o data type get loaded. But triples having e.g. ^^xsd:date format get not loaded?! Does anyone know how to deal with that issue? Examples not being…
Spooky Fox
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How to insert SPARQL data with POST request body in Blazegraph?

I'm using Blazegraph as my RDF store. I'm trying to insert data in the following format: INSERT DATA { . ... } Now, if I use the URL update parameter like…
The Coding Monk
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Do I put the ontology in blazegraph together with the data?

I'm trying to learn how to use Blazegraph. I have created an ontology and added it to the database. No problems. Blazegraph seems easy to use. Now to my question. I notice that if I query the database now, I get triples from the ontology as answers…
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Standalone blazegraph wikidata server no results returned

I just successfully create a local standalone Blazegraph instance and uploaded Wikidata database following the instruction here https://github.com/wikimedia/wikidata-query-rdf/blob/master/docs/getting-started.md. This is the "super" command I…
FranMercaes
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BINDing to inlined data provided by VALUES, and braces

I tried the following query on WDQS: SELECT ?item ?itemLabel ?string ?StringLabel ?iri ?iriLabel WHERE { VALUES ?item { wd:Q1339 } BIND( STR(?item) AS ?string ). BIND( IRI(?string) AS ?iri ). SERVICE wikibase:label { bd:serviceParam…
CXuesong
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Basic SPARQL query to return triples with label that contains string in Blazegraph

I am trying the following SPARQL query: SELECT ?uri ?label WHERE { ?uri rdfs:label "Weblex"@en . ?uri rdfs:label ?label } However, I get a cryptic error message: ERROR: SPARQL-QUERY: queryStr=SELECT ?uri ?label WHERE { ?uri rdfs:label…
MoreScratch
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How can a sparql query be prepared for a blazegraph triple store using python?

I am looking for a way in which the query can be prepared and be fired on the remote server. I know that is is feasible in Stardog and GraphDB using rdf4j in Java. But how can that be done using python for Blazegraph? I have tried looking at…
user1996684
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Querying standalone Blazegraph database returns empty

I am a complete new-be to Blazegraph and Wikidata, so, please forgive the potential triviality of my question. I have installed Blazegraph (followed instructions here ) on a Google Cloud (GC) instance. The installation went through without any…
Vistas
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How to export n-quads from blazegraph

I want to export all data from blazegraph in the typical formats. I've found a curl command for triple-format and I've found a curl command for xml/json/.. sparql result format curl -X POST…
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SPARQL SERVICE with protected endpoint

I need to use a protected endpoint to formulate a federated query in SPARQL like: select ?s ?p ?o { SERVICE { select ?s ?p ?o { ?s ?p ?o } limit 10 } } Unfortunately in the SERVICE spec there is no…
Fabio Ricci
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Handle Critical Session outside code - Java

In my project, multiple race condition scenarios are taken care by writing critical section inside the code as there is no locking mechanism available for Blazegraph database. Application is deployed in AWS Fargate(docker). Disadvantage is that we…
Linz
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