Thomas Vial posts

Archi & Techno

Graph databases: an overview

In a previous article, we introduced a few concepts related to graphs, and illustrated them with two examples using the Neo4j graph database. For the previous years, many companies have been developing graph databases -- as software vendors like Neo Technology (Neo4j), Objectivity (InfiniteGraph), Sparsity (dex*), or by building their own custom solution to integrate it into their applications, like LinkedIn or Twitter. Thus it can be hard to grasp a global picture of this rich landscape in continuous evolution. In this new article focused…

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Archi & Techno

Introduction to large-scale graph processing

Graphs are very attractive when it comes to modelling real-world data, because they are intuitive, flexible (more than tables and rows in a RDBMS), and because the theory supporting them has been maturing for centuries. As a consequence, there are several graph databases available, Neo4j being one of the most renowned. The same goes for graph processing, algorithms are numerous and well understood and have immediate applications: single-source shortest path, route finding, loop detection, subgraph matching, ... to name a few. Neo4j comes with a…

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Archi & Techno

The Esper CEP ecosystem

Mathieu’s introduction to Complex Event Processing (CEP) has announced a series of articles on various CEP solutions. We begin this series with a post about Esper. Esper, maintained by EsperTech, is a Java platform dedicated to complex event processing and event stream processing (ESP), that is, a collection of frameworks and tools that can be combined to build event-oriented applications and integrate them together. Most of the foundation of such applications is brought by the 3 different Esper packages. These are advertised as “editions”, but…

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