(1998);
Tryfona et al. (1999)
Abell?? et al. (2002);
Nguyen, Tjoa, and Wagner
(2000)
Tsois et al. (2001)
method Luj??n-Mora et al. (2002) Golfarelli et al. (1998);
H??semann et al. (2000)
Table 1. Approaches to conceptual modeling
Conceptual Modeling Solutions for the Data Warehouse
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readable by nonexpert users. In particular, they can model some constraints related
to functional dependencies (e.g., convergences and cross-dimensional attributes)
in a simpler way than UML, that requires the use of formal expressions written,
for instance, in OCL.
A comparison of the different models done by Tsois, Karayannidis, and Sellis (2001)
pointed out that, abstracting from their graphical form, the core expressivity is similar.
In confirmation of this, we show in Figure 2 how the same simple fact could be
modeled through an E/R based, an object-oriented, and an ad hoc approach.
Figure 2. The SALE fact modeled through a starER (Sapia et al., 1998), a UML class
diagram (Luj??n-Mora et al., 2002), and a fact schema (H??semann, Lechtenb?¶rger,
& Vossen, 2000)
R zz
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Idea Group Inc.
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