1. Steven Seida How Does an RDF Knowledge Store Compare to an RDBMS?

2. Graph Theory Underpins RDF Graphs (Nodes & Links) are Used to Represent a Knowledge Domain and Specifics (Instances) of It Knowledge Domain (Ontology) Television Networks Instance Data Broadcast News Programs News Articles Containing ABC ABC Nightly News Broadcasts … Competes With Fox Containing …

3. RDF vs RDBMS CriteriaKnowledge EnablementRDBM Approach Evolving problem space  - Adding knowledge representations and data is easy Adding related columns is hard, adding related tables is very hard Inference across problem domains and multiple sources*  - Intended for inference and general connectivity analysis Generally no real inferencing framework. Very hard to link data across domains. Simple query performance (simple joins and structured query) Moderate performance after tuning  - Excellent performance after tuning Social query performance (complicated joins and recursive query to traverse a large graph)  - Moderate performance after tuning Lots of software required and very brittle Lots of missing data  - Absent data is no issue Empty values are a headache *For example – Finding that a suspect terrorist had a friendship in college days with the newly appointed chief of a power plant.

4. Practical Application -An Artist’s Impression of Knowledge in a RDBMS Rose Kennedy’s Family

5. Practical Application (continued) - Knowledge in Triples (RDF) Form

6. Practical Application (continued) - With a Graph Database You add new predicates without changing any schema One-to-many relations are directly encoded without the indirection of tables You never think about what to index because all the predicates are indexed “There is no standard serialization of a relational database that will allow it to be imported into a competing relational database system without a change of semantics.” Allemang and Hendler – 2008 Semantic Web for the Working Ontologist

7. Semantic Web Vs Database Federation Database Query Engine Application Analytics User Interface … Database Identical Structures and Duplication Required! RDF Store (merge) Query Engine Typical Database Federation Semantic Web Federation Application Analytics User Interface … Webpages, Spreadsheets, Tables, Databases, etc. Converters and Scrapers RDF Stores and Files -No Duplication