SWAT Lab, Lehigh University


DLDB is a knowledge base system that extends a relational database management system with additional capabilities for DAML+OIL inference. The most significant aspect of our approach is the use of a description logic reasoner to precompute the subsumption hierarchy. The current implementation makes use of a common RDBMS (MicroSoft Access®) and the FaCT description logic reasoner. Surprisingly, this simple approach provides good results for extensional queries over a large set of DAML+OIL data that commits to a representative ontology of moderate complexity. As such, we expect such systems to be adequate for personal or small-business usage.


Zhengxiang Pan


Just download and unzip the package. DLDB is in java and runs on JDK 1.3.1 or later.

Getting started with DLDB

Please follow the readme file in the package.


This software is provided under the terms of the GNU General Public License. See the license for details.


DLDB is built on top of other sub-systems which we gratefully acknowledge: