R2RML-F: Towards Sharing and Executing Domain Logic in R2RML Mappings

Many initiatives have emerged to aid one in publishing structured resources as Linked Data on the Web with one of the major achievements being the R2RML W3C Recommendation. R2RML and its dialects assume a certain underlying technology (e.g., Core SQL 2008). This means that domain-specific data transformations – such as transforming geospatial coordinates – rely either on that underlying technology or data-preprocessing steps. We argue that one can incorporate and subsequently share that procedural domain knowledge in such mappings. Such an extension would make certain pre-processing steps redundant. One can furthermore attach metadata to these functions, which can be published as well. In this paper, we present R2RML-F, an extension to R2RML, that adopts ECMAScript for capturing domain knowledge and for which we have developed a prototype. We demonstrate the viability of the approach with a demonstration and compare its performance with different mappings in some initial experiments. Our preliminary results suggest that there is little or no overhead with respect to relying on underlying technology.