Database selection and keyword search of structured databases: powerful search for naive users

The main target of the work described in this paper is to provide a powerful approach for naive users to search structured databases. Such a study is necessary especially to satisfy Web users who expect the ability to access all Web contents in a unified way, regardless of the structure of the available information. Given a set of distributed structured databases and a query which consists of a set of keywords connected by logical operators, the approach proposed in this paper adapts both Web text files search techniques and information retrieval techniques to rank the existing databases based on their relevance to the posed query. For each keyword, the user specifies a level of search, which may be column, record, or table. We developed an estimation method with statistical foundations to estimate the usefulness of individual relational databases. The system gives a hint of what databases might be useful for the user's query, based on word-frequency information kept for each database. Some experiments have been conducted to demonstrate the effectiveness of the proposed method in determining promising sources for a given query. As naive end-user satisfaction is a main target and motive, we developed a prototype system with a user friendly Web-based interface that accomplishes our goals in a simple and powerful way.