RDF face aux défis du stockage
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I can't comment specifically on HBase, but I have implemented RDF storage for Cassandra which has a very similar BigTable -inspired data model. You basically have two options in how to store RDF data in wide-column databases like HBase and Cassandra: the resource-centric approach and the statement-centric approach. In the statement-oriented approach, each RDF statement corresponds to a row key (for instance, a UUID) and contains subject , predicate and object columns.
Storing RDF data into HBase? - Semantic Overflow
This started out as an answer at Semantic Overflow on how RDF database systems differ from other currently available NoSQL solutions. I've here expanded the answer somewhat and added some general-audience context. RDF database systems are the only standardized NoSQL solutions available at the moment, being built on a simple, uniform data model and a powerful, declarative query language . These systems offer data portability and toolchain interoperability among the dozens of competing implementations that are available at present, avoiding any need to bet the farm on a particular product or vendor. In case you're not familiar with the term, NoSQL ("Not only SQL") is a loosely-defined umbrella moniker for describing the new generation of non-relational database systems that have sprung up in the last several years. These systems tend to be inherently distributed, schema-less, and horizontally scalable.
How RDF Databases Differ from Other NoSQL Solutions - The Datagr
pius's rdf-mongo at master - GitHub
It should also be noted that prior to 1.0, there are no guarantees of backwards compatibility for data stored using previous versions of the gem. This is to make optimizing the schema for MongoDB easy. An alternative that may be examined at a later point would be to use a representation based on RDF/JSON, or JSON-LD.
RDFgrid - Map/Reduce-based Linked Data Processing with Hadoop
RDFgrid is free and unencumbered public domain software. For more information, see http://unlicense.org/ or the accompanying UNLICENSE file.
Evri Ties the Knot with Twine — Twine CEO Comments and Analysis
Today I am announcing that my company, Radar Networks , and its flagship product, Twine , have been acquired by Evri . TechCrunch broke the story here . This acquisition consolidates two leading providers of semantic discovery and search.Evri Acquires Radar Networks In Semantic Search Consolidation
Erick Schonfeld is a technology journalist and the former Editor in Chief of TechCrunch. At TechCrunch, he oversaw the editorial content of the site, helped to program the Disrupt conferences and CrunchUps, produced TCTV shows, and wrote daily for the blog. He joined TechCrunch as Co-Editor in 2007, and helped take it from a popular blog to a thriving... → Learn More After shopping itself around to all the major search engines, Radar Networks finally found a buyer in another semantic search startup.
Partitions RDF data across the Cassandra cluster based on subject URIs, improving data locality when accessing statements about a particular subject. Configuration As of Cassandra 0.6, all keyspaces and column families must be predeclared in storage-conf.xml . You can think of each used Cassandra supercolumn family as being equivalent to an RDF repository, so you'll want to configure as many as you are likely to need. This storage adapter stores RDF data in a resource-centric manner by mapping RDF subject terms to Cassandra row keys, RDF predicates to Cassandra supercolumns, and RDF object terms to Cassandra columns as follows:
RDF::Cassandra - Apache Cassandra Storage Adapter for RDF.rb
NEW YORK—Desperate fans of the recently concluded television series Lost are speculating that the program is continuing on in a parallel dimension somewhere, and that alternate versions of showrunners Damon Lindelof and Carlton Cuse are currently writing new episodes of the series. "It's very possible that a sideways world running concurrent to our own exists, and that a facsimile of myself is happy, fulfilled, and already gearing up for the season seven premiere of Lost ," said 36-year-old Kevin Molinaro, who, along with more than 20 million other hopeless fans, has recently booked multiple roundtrip tickets from Los Angeles to Australia in hopes of traveling through a vortex in the space-time continuum. "I just have to find a way to get there. We all do." According to data from Google analytics, searches for "How to build/detonate/use a hydrogen bomb to open up a multidimensional wormhole" have increased 10 millionfold since the episode aired.
'Lost' Possibly Still Airing In Parallel Dimension, Desperate Fa