Dependency-Based Query/View Synchronization upon Schema Evolutions

Query/view synchronization upon the evolution of a database schema is a critical problem that has drawn the attention of many researchers in the database community. It entails rewriting queries and views to make them continue work on the new schema version. Although several techniques have been proposed for this problem, many issues need yet to be tackled for evolutions concerning the deletion of schema constructs, hence yielding loss of information. In this paper, we propose a new methodology to rewrite queries and views whose definitions are based on information that have been lost during the schema evolution process. The methodology exploits (relaxed) functional dependencies to automatically rewrite queries and views trying to preserve their semantics.