Query By Templates: A generalized approach for visual query
		formulation for text dominated databases

		Arijit Sengupta           Andrew Dillon

Abstract

With the advent of the World Wide Web (WWW), the concept of document
databases is becoming more popular. This makes the idea
of a globally distributed digital document library realizable.
The standard encoding format for the WWW is HTML
(HyperText Markup Language), which embeds some structural information
in otherwise text-dominated documents. HTML can be viewed as a special
instance of SGML (Standard Generalized Markup Language),
a very powerful document encoding language capable of
describing may different types of languages and formats. The current
work is based on designing query languages, processing and visualizing
mechanisms for structured documents in general, and SGML documents in
particular. We are using the World Wide Web as a platform for this
querying mechanism, especially because of its popularity and
world-wide availability. However, because of the wide range of users,
these systems need to be easy to use. In particular, it is
important that users can easily search for information from the
database without prior knowledge of the internal structure of the
database. This paper outlines a visual query constructing technique
for application in databases containing hierarchically structured
documents. In this paper, we describe the visual component of this
query language, which is essentially a generalization of the Query By
Example (QBE) language for relational databases. We call
this method ``Query By Templates(QBT)''. Further, we describe the
basic properties and usefulness this visual query technique, and show
how queries on structured document databases can be performed using
this method. We also describe an implementation of QBT on the Web
using the Java{TM} programming language.