1. OpenLink Virtuoso - SQL & RDF
RDF Views of SQL Data
(Exposing SQL Data as RDF)
Orri Erling
Program Manager - OpenLink Virtuoso
© 2007 OpenLink Software, All rights reserved

2. Virtuoso Universal Server
Native SQL & XML DBMS
Federated / Hybrid Data Server (Virtual Database Engine)
Web Services Platform
SQL to RDF Mapping
Native RDF Quad Store (with SPARQL support)
In-built RDF Middleware (“Sponger”)
RDF Linked Data Deployment Platform
© 2007 OpenLink Software, All rights reserved

3. © 2007 OpenLink Software, All rights reserved
Situation Analysis
Data Drives Everything
Data Heterogeneity is a fact of life
There is no Information without Data
The Era of Information Overload is Neigh
Information Processing drives Corporate & Individual Agility
© 2007 OpenLink Software, All rights reserved

4. Final Chapter of the Information Integration Saga!
What We Hope
Write The
Final Chapter of the Information Integration Saga!
© 2007 OpenLink Software, All rights reserved

5. © 2007 OpenLink Software, All rights reserved
Yes, if...
SPARQL to Match SQL for BI Queries
Tools and Training for the Information Architect
Successful Migration of Domain Specific XML Vocabularies to RDF
© 2007 OpenLink Software, All rights reserved

6. © 2007 OpenLink Software, All rights reserved
An Ideal Solution
© 2007 OpenLink Software, All rights reserved

7. Virtuoso’s RDF Views of SQL Data Functionality
© 2007 OpenLink Software, All rights reserved

8. © 2007 OpenLink Software, All rights reserved
What are RDF Views?
Expose pre-existing relational data as virtual RDF graphs
Available for querying through SPARQL or SPASQL (SPARQL embedded in SQL)
No physical regeneration of relational data
© 2007 OpenLink Software, All rights reserved

9. Virtuoso RDF Views Implementation
Quad Patterns Translate Relational Data to G, S, P, O
Map Local or Heterogeneous Remote Data To RDF
Map XML/Text/Web Services to RDF via Table Valued Functions
Sophisticated Query Transformations and Optimization
© 2007 OpenLink Software, All rights reserved

10. Virtuoso SPARQL and SQL Extensions
Aggregates, Grouping, Full Text for SPARQL
SQL "Breakup" for Mapping Wide Rows to n-Triples
Freely Intermingle SQL and SPARQL
© 2007 OpenLink Software, All rights reserved

11. Northwind Demo Database
Tables include:
Demo.demo.Customers
Customer ID
Company Name
Contact Name
Contact
Title
Address
City
Postal Code
Country
Phone
Fax
varchar(5)
varchar(40)
varchar(30)
varchar(60)
varchar(15)
varchar(10)
varchar(24)
ALFKI
Alfreds Futterkiste
Maria Anders
Sales Represe-ntative
Obere Str. 57
Berlin
12209
Germany
ANATR
Ana Trujillo Emparedados y helados
Ana Trujillo
Owner
Avda. de la Constitucion 2222
Mexico D.F.
05021
Mexico
(5)
(5)
ANTON
Antonio Moreno Taqueria
Antonio Moreno
05023
(171)
(171)
Demo.demo.Orders
Order ID
Customer ID
Employee ID
Order
Date
Required Date
Shipped Date
Ship Via …
10643
ALFKI 6 1
10692 4 2
© 2007 OpenLink Software, All rights reserved

12. Northwind Demo Database: RDF View Definition Extract
Customer ID
Company Name
Contact Name
Contact
Title
Address
City
Postal Code
Country
Phone
Fax
Demo.demo.Customers
Northwind RDF View Definition
prefix northwind: < …
create iri class northwind:Customer < (in customer_id varchar not null)
alter quad storage virtrdf:DefaultQuadStorage
from Demo.demo.Customers as customers
from Demo.demo.Orders as orders … {
create virtrdf:NorthwindDemo as graph iri (“ { …
northwind:Customer(customers.CustomerID) a foaf:Organization as virtrdf:Customer-CustomerID ;
northwind:companyName customers.CompanyName as … ;
northwind:fax customers.Fax as virtrdf:Customer-fax .
northwind:Customer(orders.CustomerID) northwind:has_order northwind:Order(orders.OrderID) as virtrdf:Order-has_order . …
} }
© 2007 OpenLink Software, All rights reserved

13. Northwind Demo Database: RDF View Definition Extract
Order ID
Customer ID
Employee ID
Order Date
Required Date
Shipped
Date
Shipped Via …
Demo.demo.Orders
Northwind RDF View Definition
prefix northwind: < …
create iri class northwind:Order < (in order_id integer not null) .
alter quad storage virtrdf:DefaultQuadStorage
from Demo.demo.Customers as customers
from Demo.demo.Orders as orders … {
create virtrdf:NorthwindDemo as graph iri (“ { …
northwind:Order (orders.OrderID) a northwind:Order as virtrdf:Order-Order ;
northwind:orderDate orders.OrderDate as virtrdf:Order-order_date ;
northwind:requiredDate orders.RequiredDate as virtrdf:Order-required_date ;
northwind:has_customer northwind:Customer (orders.CustomerID) as virtrdf:Order-order_has_customer
northwind:has_employee northwind:Employee (orders.EmployeeID) as virtrdf:Order-order_has_employee ; …
} }
© 2007 OpenLink Software, All rights reserved

14. Northwind Demo Database: Customer Table to RDF Entity Mapping
Customer ID
Company Name
Contact Name
Contact
Title
Address
City
Postal Code
Country
Phone
Fax
ALFKI
Alfreds Futterkiste
Maria Anders
Sales Represe-ntative
Obere Str. 57
Berlin
12209
Germany
Customer/ALFKI#this
prefix <
has_customer
Order/10643#this
has_order
Order/10692#this …
companyName
contactName
contactTitle
address
city
PostalCode
country
phone
fax
Alfreds Futterkiste
Maria Anders
Sales Representative
Obere Str. 57
Berlin
12209
Germany …
Orders Table
Order ID
Customer ID …
10643
ALFKI
10692
© 2007 OpenLink Software, All rights reserved

15. Facilitate Information at Your Finger Tips
Provide a Conceptual View of Logical Data
Make the Conceptual Views concrete focal points of Data Access
Identify Data Entities using URIs (Data Links) e.g
Identify Associations / Relationships with other Entities using URIs e.g
© 2007 OpenLink Software, All rights reserved

16. SQL-RDF Mapping Experiences
Mapping is Non-Trivial
Problems Start When Many Tables Map to the Same Thing
Choice of URI Scheme Can Greatly Affect Optimization Possibilities
© 2007 OpenLink Software, All rights reserved

17. © 2007 OpenLink Software, All rights reserved
What We Need
Interop of Necessary SPARQL Extensions
Visual Tools for SQL-RDF Mapping
SQL-RDF Mapping Syntax Standardization
Community Consensus on RDF Vocabularies
© 2007 OpenLink Software, All rights reserved

18. It is NOT about RDF vs. XML vs. SQL
Web Services are for Transactions and App. Integration
RDF is for Disparate Data Meshing, Discovery, and Drill Down/Analysis
SQL is Forever
© 2007 OpenLink Software, All rights reserved

19. SQL-RDF Integration Value
Enterprise: Alleviation of heterogeneous data integration challenges
Public: A Whole Economy of Discoverable Linked Data and Data Mesh-ups
Now: Full Text For All - Next: Analysis For All
© 2007 OpenLink Software, All rights reserved

20. © 2007 OpenLink Software, All rights reserved
OpenLink Futures
Commercial Deployment of SQL to RDF Mapping
Towards Web-scale with Clustered RDBMS/Triple Store
OpenLink Data Spaces (ODS) for Bootstrapping SemWeb Presence
© 2007 OpenLink Software, All rights reserved

21. Additional Information
(general site)
(Open Source Edition Site)
(OpenLink Data Spaces)
© 2007 OpenLink Software, All rights reserved

22. © 2007 OpenLink Software, All rights reserved
Thank You!
© 2007 OpenLink Software, All rights reserved