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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What do "embedded mode" and "single server mode" in graph databases mean?

Many books and articles on graph databases talk about "embedded mode" and "single server mode". For example, the Wikipedia article on graph databases mentions the following: Blazegraph supports high availability (HA) mode, embedded mode, single…
S.M_Emamian
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How to use graph database for reputation diffusion?

I have a problem which seems to be a good fit for a graph database, but I'm uncertain of the best way to apply it. First there is a set of objects which can have directional links (a few tens of millions of them, the typical link in/out number is…
Alex I
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SPARQL BIND(COUNT(...) AS ...) not working

I'm trying to assign a count to a variable for later use in the query (SPARQL). I can't even get the following to work: SELECT ?resultsCount WHERE{ ?subject ?predicate ?object. BIND(COUNT(?object) AS ?resultsCount) } There is something…
Navigateur
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How do I schedule only one vertex to the next round in a Blazegraph GAS Program?

I'm implementing a GAS Program, but I have a doubt on how I can schedule only one vertex to the next round. What I'm trying to do involves calculating the probability of going to the next vertex and going to the one with the highest probability. So,…
antorqs
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Combine SELECT and ASK queries in a same query

Context: 14M triples, Blazegraph workbench. I'm currently attempting to design queries which combine SELECT and ASK. More exactly, I want to select results in my graph where an assumption is true. For my example, imagine I've many books which have…
Cyril
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Context parameters in Blazegraph Nano SPARQL

I am doing some experiments with the Blazegraph Nano SPARQL Server. I started the server with the following command: $ java -server -Xmx4g -jar bigdata-bundled.jar However, I need to set a timeout for queries. There is a context parameter named…
Daniel Hernández
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How do I add RDF triples to Blazegraph?

I am trying to add this simple example of RDF: Ora Lassila
Niharika Roy
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Vocabulary creation in Blazegraph

I need to create a custom geospatial datatype to represent a polygon in Blazegraph, but I can't do so as it requires defining a vocabulary for this. Would you kindly write to me the concrete steps about how to create a vocabulary in Blazegraph?
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