Abstract: Selective recovery allows a self-healing database system to undo only those operations affected by malicious transactions instead of rollbacking the whole history after malicious attacks, but this function relies on the logging mechanism's support on inter-transaction dependency tracking and longtime preservation of before image data. The inadequacy of traditional logging mechanisms and the problems of the methods used in current prototypes were analyzed.Following this, a new logging structure was proposed which contains inter-transaction dependency information and replaces the rollback segments in traditional logging mechanisms with the before image tables. Database recovery approaches based on the new mechanism were also presented. At last, we analyzed the performance and space overhead of our method, and compared it with other methods.

Key words: Self-healing, Selective recovery, Into-transaction dependency, Before image table