Browsing databases with constraint hierarchies

Electronic markets rely on database technology for efficient search for products, services, customers, and trading partners. Yet, database technology was not designed to build electronic markets, and it often fails to fully support market search activities. Market search often requires browsing and incremental search, attribute and constraint tradeoffs, approximate matches, and incorporation of user and task characteristics into searches. None of these requirements are supported directly by the database technology. Three major extensions to database technology are proposed to effectively support electronic markets. First, incremental search techniques are proposed to allow users to browse databases, and to move from solution to solution by following attribute and constraint tradeoffs. These techniques require systems to have some knowledge of similarity, distance, direction, and tradeoffs. Second, typing and stereotyping techniques are introduced to allow users to relate task and user characteristics to product attributes. These techniques require integration of typing systems with database searches. Third, a comprehensive search strategy is developed that combines incremental search and stereotyping techniques by utilizing product, task, and user ontologies.