FACILITATING COMPLEX WEB QUERIES THROUGH VISUAL USER INTERFACES AND QUERY RELAXATION

The World Wide Web can be viewed as a collection of multimedia documen ts in the form of HTML pages connected through hyperlinks. We have des igned and implemented a Web query system, WebDB, to support more compr ehensive database-like query functionalities. WebDB supports queries o n not only document level information (e.g. title, URL, keywords) but also intra-document structures (e.g. tables, forms, and images) and in ter-document linkage information (e.g. URLs and anchors) To provide hi gher usability for a system with such functionalities, we have designe d a novel visual user interface, WebIFQ (Web In-Frame-Query), to assis t users in specifying queries and visualizing query criteria including document metadata, structures, and linkage information. WebIFQ automa tically generates corresponding query statements for WebDB. As a resul t, users are not required to be aware of underlying complex schema des ign and language syntax. WebDB supports automated query relaxation to include additional terms related by semantic or co-occurrence relation ship. Alternatively, WebIFQ can facilitate users to reformulate querie s perpetually in an interactive mode. (C) 1998 Published by Elsevier S cience B.V. All rights reserved.