Study on basic steps from databases to knowledge bases

We discuss one important development of current research efforts on extensible database management system, ie., extensible query optimization, which provides a flexible platform to organize the query processing or optimization component to handle large sets of facts. We also outline a possible extension of existing processing strategy for relational DBMSs to the new and extended requirement of KBMSs and propose possible solutions for improving the evaluation efficiency of user submitted requests. Finally, we discuss the two alternative evaluation strategies for processing queries in KBMSs ie. top-down and bottom-up evaluation. Discussing their differences and commonalities is important for understanding the impact of the two methods when evaluating user requests in a KBMS environment.<>