Data Warehousing

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Introduction

Data Warehouses (DW) integrate data from multiple heterogeneous information sources and

transform them into a multidimensional representation for decision support applications. Apart from a

complex architecture, involving data sources, the data staging area, operational data stores, the global

data warehouse, the client data marts, etc., a data warehouse is also characterized by a complex

lifecycle. In a permanent design phase, the designer has to produce and maintain a conceptual model

and a usually voluminous logical schema, accompanied by a detailed physical design for efficiency

reasons. The designer must also deal with data warehouse administrative processes, which are complex

in structure, large in number and hard to code; deadlines must be met for the population of the data

warehouse and contingency actions taken in the case of errors. Finally, the evolution phase involves a

combination of design and administration tasks: as time passes, the business rules of an organization

change, new data are requested by the end users, new sources of information become available, and the

data warehouse architecture must evolve to efficiently support the decision-making process within the

organization that owns the data warehouse.

All the data warehouse components, processes and data should be tracked and administered via a

metadata repository. In [29], we presented a metadata modeling approach which enables the capturing

of the static parts of the architecture of a data warehouse. The linkage of the architecture model to

quality parameters (in the form of a quality model) and its implementation in the metadata repository

ConceptBase have been formally described in [32]. [57] presents a methodology for the exploitation of

the information found in the metadata repository and the quality-oriented evolution of a data warehouse

based on the architecture and quality model. In this paper, we complement these results with

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