Extensions of the traditional atomic transaction model are needed to support the development of multi-system applications or workflows that access heterogeneous databases and legacy application systems. Most extended transaction model-s use conditions involving events or dependencies between transactions. Intertask dependencies can serve as a uniform framework for defining extended transaction models. In this paper, we introduce event attributes needed to determine whether a dependency is enforceable and to properly schedule events in extended transaction models. Using these attributes and a formalization of a dependency into the temporal logic CTL, we can automatically synthesize an automaton that captures the computations that satisfy the given dependency. We show how a set of such automata can be combined into a scheduler that produces global computations satisfying all relevant dependencies. We show how dependencies required to implement relaxed transactions such as Sagas can be enforced and discuss briefly the issues of concurrency control, safety, and recoverability.
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