Relational Database to RDF Mapping Patterns

1. Relational Database to RDF Mapping Patterns Juan F. Sequeda1, Freddy Priyatna2 and Boris Villazon-Terrazas3 1Department of Computer Sciences, The University of Texas at Austin 2OEG-DIA, FI, Universidad Politecnica de Madrid, Spain 3iSOCO, Madrid, Spain Proposed Solution Research Question Can Relational Database to RDF (RDB2RDF) Mappings be reused to solve a commonly occurring mapping problem? Initial list of 14 reusable RDB2RDF mappings represented in R2RML syntax Motivating Example Person • How can I map a table (Person) to an ontology class (foaf:Person)? • How can I map an attribute (name) to an ontology property (foaf:name)? • How can I map several attributes (homephone, mobilephone) to an ontology property (foaf:phone)? <TripleMapPerson> a rr:TripleMap ; rr:logicalTable [ rr:tableName “Person” ]; rr:subjectMap [ rr:template “http://www.example.com/resource/Person/{id}”; rr:classfoaf:Person ]; rr:predicateObjectMap [ rr:predicatefoaf:name; rr:objectMap [ rr:column “name” ]; ] ; rr:predicateObjectMap [ rr:predicatefoaf:phone; rr:objectMap [ rr:column “homephone” ]; rr:objectMap [ rr:column “mobilephone” ]; ]. 1:1 Table Mapping 1:1 Attribute Mapping M:1 Attribute Mapping RDB2RDF Mapping Patterns Conclusion and Future Work • This is a non-exhaustive list of mapping patterns • Many mappings have different solutions in R2RML (i.e. syntactic shortcuts) • Initial observations point to a tradeoff between mapping patterns and query performance • Foresee mappings for Named Graphs, Blank Nodes for anonymous or sensitive data, Metadata, Languages, Datatypes • Invite the community to add mappings • http://mappingpedia.linkeddata.es/ Juan F. Sequeda was supported by NSF Graduate Research Fellowship. Freddy Priyatna and Boris Villazon-Terrazas were supported by PlanetData, BabelData and myBigData projects.