Research On Mapping RDF/RDFS To Relational Database Schema

Resource Description Framework (RDF) and RDF schema (RDFS) are the bases of the Semantic Web. At present, RDF and RDFS documents are widely used to describe information in the Semantic Web. How to effectively store RDF/RDFS data is becoming an important issue in the Semantic Web research.Currently, relational database is the mainstream of database application, which has the most perfect technology and is the most widely used database type. This thesis proposes to store RDF/RDFS ontologies using relational database, which can take advantage of the benefits of relational database to organize and manipulate the RDF/RDFS data. The essence of using relational database to store RDF/RDFS data is to transform RDF/RDFS data model to relational model and realize the mapping from RDF/RDFS to relational database schema.This thesis proposes a mapping method that can map RDF/RDFS to relational database schema. Firstly, the thesis gives formal definitions of the RDF/RDFS model and the relational databases schema, respectively, and then analyses the corresponding relationships between RDF/RDFS model and relational model. Secondly, a set of mapping rules are proposed according to the characteristics of schema and instances of RDF/RDFS ontologies, and mapping algorithms of classes and properties are given. These mapping rules and algorithms keep semantic information of RDF/RDFS ongologies as full as possible. Finally, a mapping system is developed based on these mapping rules and algorithms, which can map RDF/RDFS to RDB schema. Further, the feasibility and the superiority of the method are verified through experiments.