The approaches to ???strict??? conceptual modeling for DWs devised so far are summarized
in Table 1. For each model, the table shows if it is associated to some
method for conceptual design and if it is based on E/R, is object-oriented, or is an
ad hoc model.
The discussion about whether E/R-based, object-oriented, or ad hoc models are
preferable is controversial. Some claim that E/R extensions should be adopted since
(1) E/R has been tested for years; (2) designers are familiar with E/R; (3) E/R has
proven flexible and powerful enough to adapt to a variety of application domains;
and (4) several important research results were obtained for the E/R (Sapia, Blaschka,
Hofling, & Dinter, 1998; Tryfona, Busborg, & Borch Christiansen, 1999).
On the other hand, advocates of object-oriented models argue that (1) they are
more expressive and better represent static and dynamic properties of information
systems; (2) they provide powerful mechanisms for expressing requirements and
constraints; (3) object-orientation is currently the dominant trend in data modeling;
and (4) UML, in particular, is a standard and is naturally extensible (Abell??, Samos,
& Saltor, 2002; Luj??n-Mora, Trujillo, & Song, 2002). Finally, we believe that ad
hoc models compensate for the lack of familiarity from designers with the fact that
(1) they achieve better notational economy; (2) they give proper emphasis to the
peculiarities of the multidimensional model, thus (3) they are more intuitive and
E/R extension object-oriented ad hoc
no method
Franconi and Kamble
(2004b);
Sapia et al.
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