The uttermost goal of this framework
is to facilitate, manage, and optimize the design and implementation of the ETL
workflows during the initial design and deployment stage and during the continuous
evolution of the data warehouse. Despite the fact that its prototype is only a design
environment, at least for the moment, it benefits compared to the commercial ETL
tools due to the logical abstraction that it offers; on the contrary, commercial tools
are concerned directly with the physical perspective of an ETL scenario (at least to
the best of our knowledge).
Arktos II proposes a novel conceptual model for the early stages of a data warehouse
project (Vassiliadis, Simitsis, & Skiadopoulos, 2002). This model focuses on (a)
the interrelationships of attributes and concepts and (b) the necessary transformations
that need to take place during the loading of the warehouse. Also, it is able to
capture constraints and transformation composition. Due to the nature of the design
process, the features of the conceptual model are presented in a set of design steps
that constitute a methodology for the design of the conceptual part of the overall
ETL process. The construction of the model is realized in a customizable and extensible
manner, so that the designer can enrich it with the designer??™s own reoccurring
patterns for ETL transformations.
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