Predicate Rewriting for Translating Boolean Queries in a Heterogeneous Information System

摘要

Searching over heterogeneous information sources is difficult in part because of the nonuni- form query languages. Our approach is to allow users to compose Boolean queries in one rich front-end language. For each user query and target source, we transform the user query into a subsuming query that can be supported by the source but that may return extra documents. The results are then processed by a filter query to yield the correct final results.