Dependency-based concurrency control in logic-oriented object bases

A policy for scheduling concurrent transactions in which the preconditions and effects associated with the transactions can be specified is described. Also proposed is a recovery procedure for when transaction failures are detected. The advantages of the scheduling algorithm can be summarized as follows: for conventional transaction models, it is less constrained than the two-phased protocol, particularly for short transactions; and it can perform concurrency control based on semantic dependencies.<
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