Levels each stage can be analyzed at three levels or

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Levels : each stage can be analyzed at three levels or perspectives: Conceptual : it defines the DW from a conceptual point of view. Logical : it addresses logical aspects of the DW design, such as the definition of the ETL processes. Physical : it defines physical aspects of the DW, such as the storage of the logical structures in different disks, or the configuration of the database servers that support the DW. Diagrams : each stage or level require different modeling formalisms. Therefore, our approach is composed of 15 diagrams, but the DW designer does not need to define all the diagrams in each DW project: for example, if there is a straightforward map- ping between the Source Conceptual Schema (SCS) and the Data Warehouse Conceptual Schema (DWCS), the designer may not need to define the corresponding Data Map- ping (DM). In our approach, we use the UML [2] as the modeling language, because it provides enough expressiveness power to address all the diagrams. As the UML is a general modeling language, we can use the UML extension mechanisms (stereotypes, tag definitions, and constraints) to adapt the UML to specific domains. In Fig. 1, we provide the following information for each diagram: Name ( in bold face ): the name we have coined for this diagram. UML diagram: the UML diagram we use to model this DW diagram. Currently, we use class, deployment, and component diagrams. Profile ( in italic face ): the dashed boxes show the diagrams where we propose a new profile; in the other boxes, we use a standard UML diagram or a profile from other authors. Table 1. Data warehouse design framework The different diagrams of the same DW are not independent but overlapping: they depend on each other in many ways. For example, changes in one diagram may imply changes in another, and a large portion of one diagram may be created on the basis of another diagram. For example, the DM is created by importing elements from the SCS and the DWCS . In previous works, we have presented some of the diagrams and the corre- sponding profiles shown in white dashed boxes in Fig. 1: Multidimensional Profile [16,17] for the Client Conceptual Schema (CCS) and the ETL Profile [18] for the ETL Process and the Exporting Process . In light gray dashed boxes, we show our
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Fig. 1. Data warehouse design framework last contribution (submitted to review process), the Data Mapping Profile for the Data Mapping (DM) between the Source Conceptual Schema (SCS) and the Data Warehouse Conceptual Schema (DWCS), and between the DWCS and the CCS. Finally, in dark gray dashed boxes, we show the profile we are currently working on, the Database Deployment Profile , for modeling a DW at a physical level. On the other hand, the Common Warehouse Metamodel (CWM) [19] is an open industry standard of the Object Management Group (OMG) for integrat- ing data warehousing and business analysis tools, based on the use of shared metadata. This standard is based on three key industry standard: Meta Ob- ject Facility (MOF), UML, and XML Metadata Interchange (XMI). We use the
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