Database Theory - ICDT'99

Databaseresearchisa?eldofcomputersciencewheretheorymeetsapplications. Many concepts and methods, that were regarded as issues of theoretical interest when initially proposed, are now included in implemented database systems and related products. Examples abound in the ?elds of database design, query languages, query optimization, concurrency control, statistical databases, and many others. The papers contained in this volume were presented at ICDT’99, the 7th - ternationalConferenceonDatabaseThe