Establishing Logical Connectivity between Query Keywords and Database Contents

Recent advances in Internet and client-server technology provide unprecedented opportunities for users to directly access multiple databases. One major problem in this environment is that users suffer difficulties in formulation query expressions due to their unfamiliarity with the target database schemas and contents. It seems imperative that the query interface should exhibit some intelligent behavior in assisting user's query formulation process. In this work, we present a query formulation assistance system, called Qassist, which was designed to map input query keywords or phrases into various components of the database constituents. Once the mapping is performed, Qassist generates skeletons of query expressions that can be considered as plausible interpretations of the input phrases. At the core of the mapping process is the use of database schema modeling knowledge. We present an example illustrating how use of such a modeling knowledge enables us to generate the interpretations of query phrases.