Safe locking policies for dynamic databases
Vinay K. Chaudhri, Vassos Hadzilacos · 1995
It was shown by Yannakakis that a locking policy is not safe if and only if there exists a canonical non-serializable schedule of transactions running according to the rules of the policy in which all the transactions except one are executed serially [Yan82]. In the present paper, we study the generalization of this result to a dynamic database, that is, a database that may undergo insertions and deletions of entities. We illustrate the utility of this generalization by applying it to obtain correctness proofs of three locking policies that handle dynamic databases. Keywords: Concurrency Control, Correctness Issues Safe Locking Policies for Dynamic Databases 1 1 Introduction A locking policy is called safe if any concurrent execution of a set of transactions while locked according to that policy is guaranteed to be correct. Yannakakis showed that a locking policy is not safe if and only if there exists a canonical non-serializable schedule in which all transactions except one ...