Query Formulation from High-Level Concepts for Relational Databases

A new query formulation system based on a semantic graph model is presented. The graph provides a semantic model for the data in the database with userde ned relationships. The query formulator allows users to specify their requests and constraints in highlevel concepts. The query candidates are formulated based on the user input by a graph search algorithm and ranked according to a probabilistic information measure. English-like query descriptions can also be provided for users to resolve ambiguity when multiple queries are formulated from a user input. For complex queries, we introduce an incremental approach, which assists users to achieve a complex query goal by formulating a series of simple queries. A prototype system with a multimodal interface using the high-level query formulation techniques has been implemented on top of a cooperative database system (CoBase) at UCLA.