The SWRLTab is a development environment for working with SWRL rules in Protégé-OWL. It supports the editing and execution of SWRL rules. It also provides mechanisms to allow interoperation with a variety of rule engines and the incorporation of user-defined libraries of methods that can be used in rules. Several built-in libraries are provided, include collections of mathematical, string, and temporal operators, in addition to operators than can be used to effectively turn SWRL into a query language. This language provides a simple but powerful means of extracting information from OWL ontologies. Used in association with a relational data importation tool that we have developed called DataMaster, this query language can be also used to express knowledge-level queries on data imported from relational databases.
