Whereas serializability captures database consistency requirements and transaction correctness properties via a single notion, recent research has attempted to come up with correctness criteria that view these two types of requirements independently. The search for more flexible correctness criteria is partily motivated by the introduction of new transaction models that extend the traditional atomic transaction model. These extensions came about because the atomic transaction model in conjunction with serializability is found to be very constraining when used in advanced applications (e.g., design databases) that function in distributed, cooperative, and heterogeneous environments.In this article we develop a taxonomy of various correctness criteria that focus on database consistency requirements and transaction correctness properties from the viewpoint of what the different dimensions of these two are. This taxonomy allows us to categorize correctness criteria that have been proposed in the literature. To help in this categorization, we have applied a uniform specification technique, based on ACTA, to express the various criteria. Such a categorization helps shed light on the similarities and differences between different criteria and places them in perspective.
