Abstract: Query form is most widely used user interfaces for querying databases. Traditional query forms are designed and pre-defined by developers or DBA in various information management systems. With the rapid development of web information and scientific databases, modern databases become very large and complex. Therefore, it is difficult to design a set of static query forms to satisfy various ad-hoc database queries on those complex databases. In this Paper, the system proposes a Dynamic Query Form system: DQF, a query interface which is capable of dynamically generating query forms for users. The essence of DQF is to captures users preference and ranks the query components, assisting him/her to make decision. The generation of query forms is an iterative process and is guided by the user. At each iteration the system automatically generates ranking list of components and the user adds desired form componentís into the query form. The ranking of forms components is based on the capture user preference. A user can fill the query form and submit queries to view the query result at each iteration. In this way a query form could be dynamically refined till the user satisfies with query views . A probabilistic model is developed for estimating the goodness of query form in DQF.

Keywords: Query Form, User Interaction, Query Form Generation.