database recovery presents an in-depth discussion on all aspects of database recovery. firstly, it introduces the topic informally to set the intuitive understanding, and then presents a formal treatment of recovery mechanism. in the past, recovery has been treated merely as a mechanism which is implemented on an ad-hoc basis. this book elevates the recovery from a mechanism to a concept, and presents its essential properties. a book on recovery is incomplete if it does not present how recovery is practiced in commercial systems. this book, therefore, presents a detailed description of recovery mechanisms as implemented on informix, openingres, oracle, and sybase commercial database systems. database recovery is suitable as a textbook for a graduate-level course on database recovery, as a secondary text for a graduate-level course on database systems, and as a reference for researchers and practitioners in industry.