AllegroGraph supports SPARQL, RDFS++, and Prolog reasoning and clients include Goldman Sachs, Pfizer, Siemens and Wells Fargo.
Flock started out as an open-source project at Twitter and lives on through GitHub, where developers can use the software for social media and web-site use cases.
According to its GitHub page: "FlockDB is much simpler than other graph databases such as Neo4j because it tries to solve fewer problems. It scales horizontally and is designed for on-line, low-latency, high throughput environments such as web-sites."
Objectivity Inc, as the name suggests, started life in the niche object database space and went on to create InfiniteGraph.
The US software maker has since been busy creating a new graph database product called ThingSpan, focused on industrial internet of things (IoT) use cases.
ThingSpan is built to bring graph capabilities natively in to Apache Spark and the Hadoop Distributed File System (HDFS). Users can run mixed workloads on massive data sets, including navigation and pathfinding queries as well as parallel pattern-finding and predictive analytics.
A note on the Objectivity website reads: "InfiniteGraph is a highly specialized graph database. Its functionality is being migrated into ThingSpan. However, Objectivity will continue to support licensed users and will recommend it to Java developers who wish to use graph analytics outside of a Spark environment."
Teradata's Aster SQL-GR is a native graph processing engine so developers can run complex graph analysis on their data, based on bulk synchronous processing. Teradata says that Aster allows users to run graph analysis in parallel with text and statistical.
Like Oracle, Teradata stands out on this list as it isn't traditionally an open-source company. Aster analytics can be installed on native hardware and an appliance, on the Teradata cloud or on Hadoop.
Use cases include: social network/influencer analysis, fraud detection, supply chain management, network analysis and threat detection and money laundering.
Microsoft Research has been working on a graph project, previously named Trinity, since 2012, and finally released Graph Engine 1.0 for public preview in May 2015.
Graph Engine is available to Microsoft customers through Visual Studio and on the Azure cloud.
© Apache Foundation
Apache's Giraph project has also been in development since 2012. According to the Apache Foundation, it is: "An iterative graph processing system built for high scalability. For example, it is currently used at Facebook to analyse the social graph formed by users and their connections.
"Giraph originated as the open-source counterpart to Pregel, the graph processing architecture developed at Google."
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