We think you have liked this presentation. If you wish to download it, please recommend it to your friends in any social system. Share buttons are a little bit lower. Thank you!
Presentation is loading. Please wait.
Published byTerrell Passwater
Modified over 2 years ago
Relational RDF A Mapping Investigation JTC1 SC32N1639
2006-08-22Copyright © 2006 Oracle Corp.2 The Need Relational databases hold vast quantities of enterprise data That data is often needed in the context of another data model SQL/XML maps relational data to XDM (and vice versa) No extant standards effort to map relational data to the RDF data model (or vice versa)
2006-08-22Copyright © 2006 Oracle Corp.3 But Why RDF? Provide business data in a form suitable for taxonomical – and inferential – use Allow use of SPARQL[-like] facilities on such data, allow use of existing inference engines Greater participation in the Semantic Web Improve business value of enterprise data
2006-08-22Copyright © 2006 Oracle Corp.4 What Does It Mean? Literal, physical transformation: probably rare, lousy cost/benefit ratio “Lenses”: allows apps to “see” their preferred data model by transforming only desired data, only upon demand (example: SQL’s views & Oracle’s materialized views) Impedance mismatch: unavoidable, but careful design can reduce the impact
2006-08-22Copyright © 2006 Oracle Corp.5 So, What Do We Need? Standardized transformation of arbitrary relational data into RDF Obvious approach: For each row in an SQL table (or view!), create one RDF triple corresponding to each column of the row Not so simple! What about tables without keys? What about table metadata? Will apps need customized transformations, too?
2006-08-22Copyright © 2006 Oracle Corp.6 For Example C1"C2…Cn-1"Cn 100…Joe ……… 450…Sue T1 T1:R100T1:C1100 T1:R100T1:C2… ……… T1:R100T1:Cn-1… T1:R100T1:CnJoe ……… ……… T1:R450T1:C1450 T1:R450T1:C2… ……… T1:R450T1:Cn-1… T1:R450T1:CnSue PK (C1) Assumes: T1 defined as namespace (e.g., SQL://DB1/SCH1/T1)
2006-08-22Copyright © 2006 Oracle Corp.7 But… Create a “namespace declaration” for T1, or use blank nodes? Need to specify that T1 is a table, that it has n columns, the names of those columns, the data types of those columns, what the keys are, etc. Tables without keys – how to identify each row? Most RDBMSs have row IDs, but not standardized How should foreign keys be handled? What about columns of complex types? Mindless proliferation of triples!
2006-08-22Copyright © 2006 Oracle Corp.8 An Expanded Example _:t1RDF:typeSQL:TBL _:t1SQL:TblNameT1 _:t1SQL:NumCols3 _:t1SQL:Column_:c1 SQL:ColNameC1 _:c1SQL:ColTypeSQL:INT _:c1SQL:ColPos1 ……… _:t1SQL:PKnumCols1 _:t1SQL:PKcolumn_:kc1 SQL:PKcolPos1 _:kc1SQL:PKcolumn_:c1 _:t1SQL:Row_:r1 SQL:PKrow_:pk1 SQL:PKpos1 _:pk1SQL:PKval100 _:r1_:c1100 _:r1_:c2… ……… _:r1_:cn-1… _:r1_:cnJoe _:t1SQL:rowID3589122
2006-08-22Copyright © 2006 Oracle Corp.9 My Mission Ensure that SQL and XML/XQuery play well together — SUCCESS (SQL/XML) Ensure that SQL and RDF/SPARQL play well together — initial research in progress: two aspects: a) “publish” relational RDF & b) embed RDF in SQL tables, transform SPARQL to same execution trees as SQL) Can (should!) XML/XQuery and RDF/SPARQL be made to play well together? More difficult?
2006-08-22Copyright © 2006 Oracle Corp.10 Who should standardize this? H2/WG3? W3C (e.g., DAWG)? OASIS? Others? Additional approaches? Research not completed! Should I (and/or Oracle) continue? [So far, my boss’ answer is “Yes”] Lingering unresolved problems?
Dr. Leo Obrst MITRE Information Semantics Information Discovery & Understanding Command & Control Center February 6, 2014February 6, 2014February 6, 2014.
The Integration of Biological Data Using Semantic Web Technologies Susie Stephens Principal Product Manager, Life Sciences Oracle
DB glossary (focus on typical SQL RDBMS, not XQuery or SPARQL)
Digital Repositories – Linked Open Data – the possible Role of D4Science Workshop, December 2010, FAO use cases A tool to create Linked Data providers.
Limitations of the relational model 1. 2 Overview application areas for which the relational model is inadequate - reasons drawbacks of relational DBMSs.
Querying on the Web: XQuery, RDQL, SparQL Semantic Web - Spring 2006 Computer Engineering Department Sharif University of Technology.
RDF and RDB 1 Some slides adapted from a presentation by Ivan Herman at the Semantic Technology & Business Conference, 2012.
XML: Extensible Markup Language
Database Management Systems, R. Ramakrishnan and J. Gehrke1 The Relational Model Chapter 3.
Michael Povolotsky CMSC491s/691s. What is Virtuoso? Virtuoso, known as Virtuoso Universal Server, is a multi-protocol RDBMS Includes an object-relational.
© 2008 Hewlett-Packard Development Company, L.P. The information contained herein is subject to change without notice Enterprise Information Integration.
The Relational Model Class 2 Book Chapter 3 Relational Data Model Relational Query Language (DDL + DML) Integrity Constraints (IC) (From ER to Relational)
A division of Publishing Technology Facet Building Web Pages With SPARQL SWIG-UK Event, HP Labs November 23 rd 2007 Leigh Dodds Chief Technology Officer,
2005rel-xml-ii1 The SilkRoute system The system goals Scenario, examples View Forests View forest and query composition View forest efficient.
1 Relational Model. 2 Relational Database: Definitions Relational database: a set of relations Relation: made up of 2 parts: – Instance : a table,
The Relational Model Lecture 3 Book Chapter 3 Relational Data Model Relational Query Language (DDL + DML) Integrity Constraints (IC) From ER to Relational.
1 Lecture 13: Database Heterogeneity. 2 Outline Database Integration Wrappers Mediators Integration Conflicts.
Attribute databases. GIS Definition Diagram Output Query Results.
Indexing XML Data Stored in a Relational Database VLDB`2004 Shankar Pal, Istvan Cseri, Gideon Schaller, Oliver Seeliger, Leo Giakoumakis, Vasili Vasili.
© 2018 SlidePlayer.com Inc. All rights reserved.