The first phase of the planning demands to define and to document the outline of the level of they give to you operational to leave from which it will come fed the Datamart.
It is necessary therefore to analyze and to comprise the outlines of sources available (recognition), eventually to transform them in order to carry to the light previously unexpressed useful correlations (normalization), to determine which portions they are useful to the ends of the decisional process in the business field which the date mart is dedicated, and finally to estimate the quality of give to you.

In case the sources had more to be than one, their outlines will have to be subordinates to one homogenization of give and stiff integration to you to characterize the features common and to heal the eventual inconsistenze.
It is not the situation of the case in examination, in which there is an only source, that is the database of the MV.

In case instead the Datamart of the Virtual Warehouse it had to leave directly from the database relational of the present companies in the Industrial District, the task would be extremely more difficult and longer.
In a District, less than particular and extremely fortuitous circumstances, myriads of systems exist owners; the options could be two: to replace the single systems with an only operational system, that District would mainly have sense in a wider speech regarding the plan of Virtual Warehouse (Net), or to make to maintain the systems in use and to dedicate much time to this phase of the planning.

To the end of this phase the result is the reconciled outline of the sources of gives to you; in our case the result is the Outline Entity Relations, that it is to the base of the database of the Virtual Warehouse.