A Database-to-Ontology Mapping Language and Tool

overview The RDB2OWL mapping language allows specifying relational database to OWL ontology mappings by supplying the database object correspondence information within annotations to the ontology and its entities (e.g. OWL classes, object and data properties).
The RDB2OWL tool processes an ontology annotated with RDB2OWL mapping annotations to produce either:
  1. a D2RQ mapping for turning the database into a SPARQL endpoint or producing dump of RDF triples of database contents, or
  2. (experimental) a custom SQL script for RDF triple dump creation.

The diagram shows an example mini-University ontology in OWLGrEd ontology editor notation, enriched with visual profile (plugin) for RDB2OWL annotation rendering.
The example ontology in OWL RDF/XML format is available here.
A corresponding example database creation script (MS SQL Server) is available here.

requires Windows XP SP2 or later

language Add RDB2OWL annotations using the annotation property rdb2owl:DBExpr, where rdb2owl stands for <http://rdb2owl.lumii.lv/2012/1.0/rdb2owl#>, to the ontology itself and its entities (classes, object and data properties).

Consult language overview and publications [1], [2] and [3] for the RDB2OWL language description.

download RDB2OWL annotation processing tool
(Optional) OWLGrEd/DBExpr editor with RDB2OWL annotation plugin

use cases Relational database semantic re-engineering

instructions 1. Download and unzip RDB2OWL tool anywhere on your computer.
2. Locate or create RDB to be connected (JDBC driver class, connection string), place the driver itself in /lib/jdbc folder of RDB2OWL application  (example DB creation script, MS SQL Server).
3. Locate or create OWL ontology with RDB2OWL annotations pointing to the located RDB and its schema elements (example, adjust connection string parameters).
4. Click on start.bat in the RDB2OWL application folder
5. Choose 'Create mapping from ontology', or 'Step by step mapping generation' with the involved steps 'Load ontology'. 'Load source database schemas', 'Finalize abstract mapping' and 'Generate D2RQ mapping'; tick check-box 'with inference', if the D2RQ mapping is used for on-the-fly database access
6. Use generated D2RQ mapping for DB-corresponding RDF triple dump or on-the-fly SPARQL endpoint access within D2RQ platform technologies; we recommend D2RQ working version 0.8.2 (D2RQ master branch snapshot).

  • Kārlis Čerāns, Professor
  • Guntars Būmans, Researcher
  • Jūlija Ovčiņņikova, Graduate student

try also OWLGrEd Graphical OWL ontology visualization and authoring tool
ViziQuer A graphical SPARQL generation tool
OBIS Ontology Based Information System, a tool for UI generation for information systems backed by a SPARQL endpoint

licence RDB2OWL is free use tool for personal, academic and evaluation purposes. To obtain other (including commercial) licence, contact us at rdb2owl@lumii.lv .

contact rdb2owl@lumii.lv