The conceptual model is not a workflow; instead, it simply identifies the mappings and the transformations needed in an ETL process. The placement of the transformations into the conceptual design does not directly specify their execution order. However, the logical model represents a workflow and thus, it is very important to determine the execution order of the activities. To tackle this, we provide a method for the semi-automatic determination of a correct execution order of the activities in the logical model, wherever this is feasible, by grouping the transformations of the conceptual design into stages of order-equivalent transformations.
Finally, with the goal of formalizing the mapping between the two models and dealing with the aforementioned problems, we present a sequence of steps that constitutes the method for the transition from the conceptual to the logical model.