XML(eXtensible Markup Language) has recently emerged as a new standard for data representation and exchange on the Internet. Web servers and applications encoding their data in XML can quickly make their information available in a simple and usable format, and such information providers can interaction easily. Information content is separated from information rendering, making it easy to provide multiple views of the same data. Most of us are familiar with web sites that contain vast databases of useful information, but whose query and search facilities are surprisingly primitive.
This thesis proposes web agent for information retrieval and information extraction from DBMSs(Database Management System) using table-list mapping method. Web agent accesses database using information, such as IP address, port number, database name and password. After web server is connected with database, it takes data using query sentence. Web server transforms data to XML DTD(Document Type Definition) by table-list mapping method. Table-list mapping method using Scheme language, it is easy to process vast data at once.
Web server makes XML document from source database data, XML document saves destination database. Using these methods, web agent exchange data between heterogeneous databases. It is easy to manage data on the web, exchange data between heterogeneous DBMSs using XML and Scheme language.