2. Who am I
Software consultant (CoffeeCupConsulting)
BG JUG board member (http://jug.bg)
OpenJDK and Oracle RBDMS enthusiast
Twitter: @martin_fmi
Martin Toshev Prague, 19-20 October 2017
3. Agenda
Semantic web at a glance
Semantic technology in Oracle RDBMS 12c
Oracle RDBMS12c vs triple stores
Martin Toshev Prague, 19-20 October 2017
5. Semantic Web
•A set of standards providing an extension of the world wide web
•Promote the idea of a global “web of linked data”
•Defined using RDF as a base format
•One of the building blocks of Web 3.0
Martin Toshev Prague, 19-20 October 2017
<http://data.bgoug.online/people
/MartinToshev>
<http://data.bgoug.online
/events/100>
foaf:Person
<http://data.bgoug.online/attends>
rdf:type
6. RDF
• RDF represents information in a subject-predicate-object form
• Resources are identified with URIs
• RDFS provides a mechanism for definition of RDF vocabularies
Martin Toshev Prague, 19-20 October 2017
<http://data.bgoug.online/people/MartinToshev>
<http://data.bgoug.online/attends>
<http://data.bgoug.online/events/100>
http://data.bgoug.online/bg/events/10
<http://data.bgoug.online/attendee>
<rdfs:label>
“Conference attendee”
7. SPARQL
• SPARQL is the standard RDF query language
• The DML extension of SPARQL is called SPARUL
Martin Toshev Prague, 19-20 October 2017
SELECT ?s ?p ?o FROM <data.bgoug.online/graph> WHERE { ?s ?p ?o }
INSERT {
GRAPH <data.bgoug.online/graph> {
<http://data.bgoug.online/people/MartinToshev>
<http://data.bgoug.online/attends>
<http://data.bgoug.online/events/100>
}
}
8. OWL & SKOS
• SKOS provides a way to create knowledge organization systems using RDF
• These include taxonomies, thesauri, classification schemes etc.
• OWL provides an RDF representation of ontologies
• Defines semantic of the RDF schema
• Far more complex than SKOS for knowledge organization
Martin Toshev Prague, 19-20 October 2017
9. Semantic Data
• Semantic data might be encoded within an existing web page
• One option is to use RDFa which is an attribute-level HTML extension
Martin Toshev Prague, 19-20 October 2017
<div xmlns:dc="http://purl.org/dc/elements/1.1/"
about=" http://data.bgoug.online/events/100">
<span property="dc:title">BGOUG Autumn Conference 2017</span>
<span property="dc:creator">BGOUG</span>
<span property="dc:date">2017-11-19</span>
</div>
10. Semantic Data
• Semantic data might be exposed via web-accessible databases
• These are also called triple/quad stores
• Provide native storage for RDF data
• Widely used implementations are Virtuoso, GraphDB and Blazegraph
Martin Toshev Prague, 19-20 October 2017
13. Why Oracle Semantic Technology ?
• Existing Oracle database provide a great source of data
• Some of that data can might be exposed as Linked Open Data
• Semantics may be applied on top of relational data
• Semantic data might be stored in a relational format
Martin Toshev Prague, 19-20 October 2017
14. Use case: social networking
• Cisco WebEx social platform uses Oracle semantic technology
• Social graph is represented by a unified RDF model
• Enables semantic tagging, social graph navigation and search
• Provides connectivity with other sources of semantic data
Martin Toshev Prague, 19-20 October 2017
15. General features
• Native RDF/RDFS/OWL/SKOS support
• Bulk load of RDF data
• Triples are stored in database tables in the MDSYS schema
• Information about models stored in the MDSYS.SEM_MODEL$ view
• Improved performance and scalability
Martin Toshev Prague, 19-20 October 2017
16. General features
•SPARQL-like queries via SQL (along with a Java API)
•SPARQL support via Jena and SESAME providers
•Semantic rules (inference) and entailments
•Virtual semantic models
Martin Toshev Prague, 19-20 October 2017
17. SQL-based semantic queries
• Provided by a DSL that mimics the SPARQL capabilities
• Implemented by the SEM_MATCH table function
• Ontology-based querying of relational data via the SEM_RELATED operator
• Provides SPARQL constructs such as FILTER and OPTIONAL
• New SPARQL-like features added per RDBMS release
Martin Toshev Prague, 19-20 October 2017
18. Enabling semantic features
1) EXECUTE mdsys.enableGeoRaster;
2) SQL*Plus: @%ORACLE_HOME%mdadmincatsem.sql
3) (change password of MDSYS):
alter user mdsys identified by mdsys account unlock;
alter user mdsys identified by pass123;
Martin Toshev Prague, 19-20 October 2017
21. Oracle RDBMS 12c
• Mixing relational and RDF data provides advanced query capabilities
• A lot of PL/SQL subprograms provided by the SEM_APIS package
Martin Toshev Prague, 19-20 October 2017
22. Triple store
• Dedicated format for storing of RDF data
• Provides more specialized optimization capabilities for SPARQL queries
• Provide dedicated management tools and interfaces for RDF data
Martin Toshev Prague, 19-20 October 2017
23. Summary
• Oracle Database 12c already provides a solid set of semantic features
• Existing relational data can be amended with semantic information
• Oracle database can be used as a triple store
Martin Toshev Prague, 19-20 October 2017
25. References
Oracle Database 11g Semantic Technologies Overview
http://download.oracle.com/otndocs/tech/semantic_web/pdf/oow10_semtech_
Spatial and Graph RDF Semantic Graph Developer’s Guide
https://docs.oracle.com/database/121/RDFRM/rdf-overview.htm#RDFRM100
Oracle Database Semantic Technologies
http://www.oracle.com/technetwork/database/options/semantic-
tech/semtech11gr2-featover-131765.pdf
Martin Toshev Prague, 19-20 October 2017
26. References
How and Why Customers Use Oracle's Semantic Database
Technologies: A Panel
http://download.oracle.com/otndocs/tech/semantic_web/pdf/oow10_sem
tech_intro_lopez.pdf
Oracle Spatial 11g use in Cisco Social Semantic Software
http://download.oracle.com/otndocs/tech/semantic_web/pdf/oow10_sem
tech_cisco.pdf
RDF Semantic Graph - Training
http://www.oracle.com/technetwork/database/options/spatialandgraph/le
arnmore/semtech-training-100336.html#training
Martin Toshev Prague, 19-20 October 2017
27. References
Cisco WebEx Social
Oracle Spatial and Graph: Graph for Enterprise Collaboration
http://download.oracle.com/otndocs/tech/semantic_web/pdf/case_studie
s/Oracle_CaseStudy_Cisco_WebEx_Social_RDF_Graph_Enterprise_Collabor
ation.pdf
Martin Toshev Prague, 19-20 October 2017
Editor's Notes
TLS being the predecessor of SSL is not interoperable with SSL …
TLS being the predecessor of SSL is not interoperable with SSL …
TLS being the predecessor of SSL is not interoperable with SSL …
TLS being the predecessor of SSL is not interoperable with SSL …
TLS being the predecessor of SSL is not interoperable with SSL …
TLS being the predecessor of SSL is not interoperable with SSL …