Semantic OSTRICH

This is a prototypical proof-of-concept implementation for semantic versioned querying. It is implemented on top of the versioned triple store, OSTRICH. An additional layer is able to perform inferencing based on a set of rules.

Run on command line

This package ships with a command line tool to execute semantic triple pattern queries against OSTRICH dataset and language stores, based on a set of inference rules.

The following executes a semantic version materialization on dataset version 88 and language version 0 for the triple pattern <http://dbpedia.org/resource/Doctor_Who_(series_9)> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> ?o. This will use the N3 rules from rules.n3.

$ semantic-ostrich bin/semantic-ostrich data/evalrun-bearb-day-data.ostrich/ data/evalrun-bearb-day-language.ostrich/ rules.n3 --vd 88 --vl 0 --qvm '<http://dbpedia.org/resource/Doctor_Who_(series_9)> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> ?o'

For example, a rules file could contain this:

{
  ?c <http://www.w3.org/2000/01/rdf-schema#subClassOf> ?d.
  ?x a ?c.
} => {
  ?x a ?d.
}.

For more information on the command line tool, call semantic-ostrich --help.

Use in an application

// Initialize
const SemanticOstrich = require('semantic-ostrich');
ostrichStore = new SemanticOstrich();
await ostrichStore.init('path/to/datastore.ostrich', 'path/to/languagestore.ostrich', true); // The last parameter sets it to the more performant readonly mode
const rules = SemanticOstrich.readRules('path/to/rules.n3');

// Query one version
const subject = 'http://dbpedia.org/resource/Doctor_Who_(series_9)';
const predicate = 'http://www.w3.org/1999/02/22-rdf-syntax-ns#type';
const object = null; // variable
triples = await ostrichStore.semanticSearchTriplesVersionMaterialized(rules, subject, predicate, object, { version: 88 }, { version: 0 });

See bin/semantic-ostrich for a more extensive example of the usage of SemanticOstrich.

License

This software is written by Ruben Taelman.

This code is copyrighted by Ghent University – imec and released under the MIT license.