Abstract: The present invention generally is directed to a system, method and article of manufacture for accessing data independent of the particular manner in which the data is physically represented. In one embodiment, a data repository abstraction layer provides a logical view of the underlying data repository that is independent of the particular manner of data representation. A query abstraction layer is also provided and is based on the data repository abstraction layer. A runtime component performs translation of an abstract query into a form that can be used against a particular physical data representation.

Abstract: Methods, articles of manufacture and systems for managing execution of a multi-step workflow in which one or more steps are repeatedly executed on data of a database. One embodiment provides a method comprising receiving current input for execution of a step of the workflow on relevant data of the database, wherein the step has been previously executed on the relevant data using previous input identical to the current input and wherein the previous execution of the step produced previous output; determining whether the step is deterministic, whereby the step generates identical output for given input in repeated executions of the step on the relevant data; and, if the step is deterministic, returning the previous output produced during the previous execution of the step without re-executing the step.