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tions, and discusses which architectural patterns should be used to solve those requirements. It further
describes how the concept of service-orientation may inuence future data warehouse architectures and
solutions as well.
Chapter 2, Improving Expressive Power in Modeling Data Warehouse and OLAP Applications, by
Elzbieta Malinowski, discusses how the conceptual multidimensional model can be used to facilitate
the representation of complex hierarchies and different kinds of dimensions in comparison to their
representation in a relational model and commercial OLAP tools. This chapter is in itself an excellent
reference on multidimensional modeling, representation and implementation issues.
Chapter 3, From Conventional to Multiversion Data Warehouse: Practical Issues, by Khurram
Shahzad, concerns data warehouse versioning. Versioning is quite important in real-world projects, since
operational sources or the data warehouse structure itself may evolve. Conventional data warehouses
are not prepared to handle these modications. The chapter, while not a comprehensive survey on the
subject, takes a very practical perspective, collecting and integrating concepts, issues and solutions of
multiversion data warehouses in a tutorial-like approach, to provide a unied source for users that need
to understand version functionality and mechanisms.
Chapter 4, Compression Schemes of High Dimensional Data for MOLAP, by K. M. Azharul Hasan,
surveys data compression techniques relevant to multidimensional OLAP and discusses important
quality issues of MOLAP compression and of existing techniques. Compression is indeed an important
issue faced in implementations of data warehouses and in particular for multidimensional OLAP, due
to possibly huge size and sparsity of MOLAP representations.
Section 2. Application Issues and Trends in Data Warehousing and OLAP
Chapter 5, View Management Techniques and Their Application to Data Stream Management, by Chris-
toph Quix et al., is a very interesting and insightful chapter on the subjects of view management and
data stream management, starting with a suggestion that data stream processing shares many similarities
with view management in data warehousing. The chapter provides an overview of view maintenance and
view selection methods, explains the fundamental issues of data stream management, and discusses how
view management techniques from data warehousing are related to data stream management. Finally, it
provides directions for future research in view management, data streams, and data warehousing.
Chapter 6, A Framework for Data Warehousing and Mining in Sensor Stream Application Domains,
by Nan Jiang provides insight into how data collected from sensor devices can be fed into data ware-
houses and mined. This is a relevant subject, since sensors are increasingly used in many different ap-
plications, from weather and environmental monitoring to hospital and factory operation sites, trafc
monitoring and so on. The chapter presents a general framework for domain-driven mining of sensor
stream applications, and evaluates the proposed framework with experiments on trafc management
and environmental monitoring.
Chapter 7, A Data Warehousing Approach for Genomics Data Meta-Analysis, by Martine Collard et
al., takes a very different application domain, genomics, and shows how data warehousing and mining
are relevant in that context. Since experimental micro-array data and sources of biological knowledge
are now available on public repositories, comparative analyses involving several experiments become
conceivable and hold potentially relevant knowledge. However, manually navigating and searching for
similar tendencies in such huge spaces is impracticable. In this context, the authors propose a semantic
data warehousing solution based on semantic web technologies that allows to monitoring both the di-
versity and the volume of all related data.