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The World of Knowledge Graphs in Oracle Databases

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The World of Knowledge Graphs in Oracle Databases The World of Knowledge Graphs in Oracle Databases Collaboration between Semantic Web Company and Oracle Emma Thomas Sebastian Gabler Principal Solutions Architect Director of Sales Oracle A-team Semantic Web Company November 19th 2019 2 Confidential – © 2019 Oracle Restricted Safe Harbor Statement The following is intended to outline our general product direction. It is intended for information purposes only, and may not be incorporated into any contract. It is not a commitment to deliver any material, code, or functionality, and should not be relied upon in making purchasing decisions. The development, release, timing, and pricing of any features or functionality described for Oracle’s products may change and remains at the sole discretion of Oracle Corporation. 3 The World of Knowledge Graphs in Oracle Databases Introduction to Knowledge Graphs Oracle Database Spatial and Graph - RDF Focus Oracle RDF4J adapter Using PoolParty for Search, Similarity, Recommendation and Visualisation 4 Confidential – © 2019 Oracle Restricted Graphs are Everywhere Heiko Paulheim. Journal of Web Semantics: Special Issue on Knowledge Graph Refinement. “Knowledge Graph Refinement: A Survey of Approaches and Evaluation Methods.” [September, 2016] 5 Confidential – © 2019 Oracle Restricted An Opte Project Visualisation of routing paths through a portion of the Internet By The Opte Project - Originally from the English Wikipedia; description page is/was here., CC BY 2.5, https://commons.wikimedia.org/w/index.php?cu rid=1538544 6 What is a Knowledge Graph? Knowledge graphs are large networks of entities, their semantic types, properties, and relationships between entities1. Key Features: Knowledge “Things, not strings” Database Base Knowledge global unique identifiers Graph Formal structure/semantics machine processable, unambiguous Linked descriptions Graph resources are described by their connections 1. M. Kroetsch and G. Weikum. Journal of Web Semantics: Special Issue on Knowledge Graphs. http://www.websemanticsjournal.org/index.php/ps/an 7 Confidential – © 2019 Oracle Restricted nouncement/view/19 [August, 2016] Data Storage Name Desc Product in-a has-a Category SKU Image Relational Hierarchical Graph 8 The Semantic Web and Graph Databases “I have a dream for the Web [in which computers] become capable of analyzing all the data on the Web – the content, links, and transactions between people and computers. A "Semantic Web", which makes this possible, has yet to emerge, but when it does, the day- to-day mechanisms of trade, bureaucracy and our daily lives will be handled by machines talking to machines. The "intelligent agents" people have touted for ages will finally materialize” Tim Berners-Lee, 1999 9 Confidential – © 2019 Oracle Restricted W3C Standards for Knowledge Graphs The W3C (World Wide Web Consortium) has defined a suite of standards to support Linked Data and Knowledge Graphs. Fundamental Concepts are: • Globally Unique IDs: URI • Links to other resources • Standard Data Model: RDF • Standard Ontology Language: OWL • Standard Query Language: SPARQL 10 Resource Description Framework (RDF) An RDF graph is a directed, labeled graph with some syntactic restrictions ● Edge labels are URIs ● Source vertex for an edge must be a URI ● Destination vertex is a URI or a scalar value An edge is the atomic unit of an RDF graph – called an RDF triple RDF Triple 11 Confidential – © 2019 Oracle Restricted Modeling Vocabularies With the Semantic Web, vocabularies define the concepts and relationships (also referred to as “terms”) used to describe and represent an area of concern: RDFS Resource Description Framework Schema allows you to express the relationships between things by standardizing on a flexible, triple-based format and then providing a vocabulary. OWL Web Ontology Language is an ontology language. The semantic web standard that is used to defined ontologies (metadata sets) so that they can be used and understood in that environment. Owls purpose is to develop ontologies that are compatible with the world wide web, where an ontology is definition and classification of concepts and entities and the relationship between them 12 Confidential – © 2019 Oracle Restricted Modeling Vocabularies SKOS stands for Simple Knowledge Organisation System. The name SKOS was chosen to emphasise the goal of providing a simple yet powerful framework for expressing knowledge organisation systems in a machine- understandable way. SKOS provides a standard way to represent knowledge organization systems using the Resource Description Framework (RDF). Encoding this information in RDF allows it to be passed between computer applications in an interoperable way. 13 Confidential – © 2019 Oracle Restricted SPARQL SELECT ?name WHERE { ?s a onto:Employee . ?s dcterms:title ?name } 14 Confidential – © 2019 Oracle Restricted Recap: Description of a Knowledge Graph Knowledge graphs provide holistic knowledge, including ▹ instance data (ground truth), either open, private, or closed ▹ schema data (vocabularies, ontologies) ▹ metadata (e.g. provenance, versioning, licensing) ▹ comprehensive taxonomies to categorize entities ▹ links between internal and external data ▹ mappings to data and documents stored in other systems and databases Source: Sören Auer, Fraunhofer IAI 15 Confidential – © 2019 Oracle Restricted The World of Knowledge Graphs in Oracle Databases Introduction to Knowledge Graphs Oracle Database Spatial and Graph - RDF Focus Oracle RDF4J adapter Using PoolParty for Search, Similarity, Recommendation and Visualisation 16 Confidential – © 2019 Oracle Restricted Database Version and Options for RDF Knowledge Graph ▪ On-premise ▪ Oracle Database Enterprise Edition with Spatial & Graph and Partitioning options ▪ Oracle Database Cloud Services ▪ DBCS (Bare Metal & VM) ▪ Exadata Cloud Service ▪ Exadata Cloud at Customer ▪ ATP-Dedicated (planned) 17 Copyright © 2019, Oracle and/or its affiliates. All rights reserved. Oracle Spatial and Graph 19c – RDF Knowledge Graph Features • Fast bulk-load and indexing Load / • RDF view of Relational data RDF Knowledge Graph Storage • Manages over a trillion quads Leverages Oracle capabilities: • SPARQL-Jena/Fuseki RAC & Exadata scalability Query • SPARQL-in-SQL query & update • Federated query Compression & partitioning • GeoSPARQL In-Memory Column Store SQL*Loader direct path load • RDFS, OWL2 RL, EL, SKOS • Ladder-based inference Parallel DDL, DML, and query Reasoning • Incremental, parallel reasoning RMAN Backup and Recovery • User-defined rules High Availability - Data Guard + DR • Plug-in architecture Oracle Label security Analytics • OBIEE Manageability - Enterprise Manager • Oracle Advanced Analytics Logical Standby • PGX 18 Copyright © 2019, Oracle and/or its affiliates. All rights reserved. Big Data Graph Benchmark 1 Trillion Triple RDF Benchmark with Oracle Spatial and Graph Oracle Database can load, query and inference millions of RDF graph edges per second World’s fastest data loading performance World’s fastest query performance Worlds fastest inference performance Massive scalability: 1.08 trillion edges Platform: Oracle Exadata X4-2 Database Machine Source: w3.org/wiki/LargeTripleStores 19 Confidential – © 2019 Oracle Restricted Oracle Spatial and Graph 19c – RDF Knowledge Graph Architecture SQL Developer Enterprise Manager Protégé Plugin Fuseki Endpoint Cytoscape Plugin RDF Support and Other DB Tools Support for Apache Jena (Java API) SQL and PL/SQL API RDF Bulk Loader Forward-chaining SPARQL-to-SQL SPARQL Update OWL Reasoner Query Translator Processor Generic Relational Schema for RDF Views of Relational Data Storing RDF Data 20 Confidential – © 2019 Oracle Restricted What makes a store RDF ready? It implements at least one of the RDF ready libraries/frameworks: • Eclipse RDF4J • Apache Jena It offers a SPARQL endpoint to query the database using SPARQL 21 Confidential – © 2019 Oracle Restricted Oracle Spatial and Graph - Apache Jena Oracle Database Release 18c offers support for: • Apache Jena 3.1 • Apache Jena Fuseki 2.4 • Protege 5.2 Available adapters: Source: Oracle Spatial and Graph downloads 22 Confidential – © 2019 Oracle Restricted The World of Knowledge Graphs in Oracle Databases Introduction to Knowledge Graphs Oracle Database Spatial and Graph - RDF Focus Oracle RDF4J adapter Using PoolParty for Search, Similarity, Recommendation and Visualisation 23 Confidential – © 2019 Oracle Restricted Oracle RDF4J Adapter Collaboration work between Semantic Web Company and the Oracle A-Team to create a new adapter for the Java based RDF4J library. RDF4J capabilities brings: • Community opportunity - RDF4J GitHub repo • Easy access to the Java community • Easy access and tested with PoolParty Semantic Suite 24 Confidential – © 2019 Oracle Restricted Oracle RDF4J Adapter 25 Confidential – © 2019 Oracle Restricted The World of Knowledge Graphs in Oracle Databases Introduction to Oracle Spatial and Graph Core Graph Database Features Oracle RDF4J Using PoolParty for Search, Similarity, Recommendation and Visualisation 26 Confidential – © 2019 Oracle Internal/Restricted/Highly Restricted Introducing Semantic Web Company Founded in 2004 Developer & Vendor of SWC named to KMWorld’s Based in Vienna PoolParty Semantic Suite ‘100 Companies That Matter in Privately held Participating in projects with Knowledge €2.5 million Management’ in 2016, until 2019 50+ FTE funding for R&D Software Engineers & ISO 27001:2013 Consultants for NLP, ~35% certified Semantics and Machine revenue growth/year learning 9,000 followers 27 PoolParty
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