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assisting the integration of heterogeneous databases.
F D3 is based in a logic which allows the descrip-
tion of the FDs contained in the local database sys-
tems and the construction of a unified global sys-
tem. To communicate the information collected in the
global model, we introduce a High Level Functional
Dependencies (HLFD) Data Model which is used in
a similar way as the Entity/Relationship Model. The
HLFD data model can be deduced automatically from
a EFD logic theory. Furthermore, it is possible to
translate automatically the HLFD data model into a
relational database.
In (Cordero et al., 2002a), we introduce a new
axiomatic system for FD logics, named SL
F D
par-
ticularly designed to remove redundancy. We de-
fine two substitution operators and we illustrate their
behaviour for removing redundancy. The new sys-
tem improves the FD logic presented in (Enciso and
Mora, 2002) and it is equivalent to Armstrong’s ax-
ioms (Armstrong, 1974). We also showed that SL
F D
is more adequate for the applications.
In (Mora et al., 2003) we introduce a pre-
processing transformation based on SL
F D
which re-
moves redundancy in a given set of Functional De-
pendencies and allows a more efficient further man-
agement by other well known algorithms (Atzeni and
Torlone, 1997; Biskup and Convent, 1991; ?). We
have carried out an empirical study to prove the prac-
tical benefits of our approach.
In this paper, we present Attribute/Dependencies
(A/D) CASE, a case tool which apply the result cited
above in the area of heterogeneous database inte-
gration and in database cooperative design (Cordero
et al., 2002b). A/D CASE includes a High Level
Functional Dependencies (HLFD) Data Model which
can be deduced from the global data dictionary, using
automated reverse engineering.
This paper is organized as follows: in section 2 we
summarize the F D3 architecture presented in (En-
ciso and Mora, 2002). Section 3 introduces SL
F D
as the new heart of the F D3, and section 4 presents
the pre-processing transformation which removes re-
dundancy in a given set of Functional Dependencies.
The AD/CASE tool is showed in section 5. Section 6
outlines the conclusions and future works.
2 FD3 ARCHITECTURE
As was argued in (Bertino et al., 2001), to facili-
tate user participation, we need new tools (easier to
use and more powerful) and new techniques (includ-
ing new data models). In this paper, we present At-
tribute/Dependencies (A/D) CASE, a case tool to de-
sign databases in a heterogeneous environment.
A/D CASE allows to put in practice the F D3 archi-
Figure 1: The Functional Dependencies Data Dictionary
tecture presented in (Enciso and Mora, 2002). F D3
turns around a simple element: The Functional De-
pendence (FD). The FD notion is inherent to most
used database models (hierarchical, network, rela-
tional,etc.). Figure 1 shows briefly the F D3 archi-
tecture presented. The main characteristic of our ar-
chitecture is the use of logic in all the stages: analysis,
design, model transformation, integration, etc.
F D3 allows the generation of a global data model
as follows:
1. (i) We extracts some FD’s automatically from the
conceptual data model (structural FDs), (ii) the
designer adds other FDs which corresponds to re-
quirements of the information system (environment
FDs). The local data dictionaries will be formally
represented using an FD logic.
2. F D3 is the union (integration) of all the FD sub-
theories (local data dictionaries), rendering an inte-
grated FD logic theory.
3. F D3 is depurated and we remove redundancy by
applying the preprocessing transformation that we
propose in (Mora et al., 2003). We obtain the Depu-
rated FD logic theory which corresponds to the
global schema of the heterogeneous database.
4. Finally, we may deduce a high level data
model, named High Level Functional Dependen-
cies (HLFD) data model from the integrated FD
logic theory . The HLFD data model allows us to
obtain a global vision of the whole system with a
strong level of abstraction. The designer has a high
level data model that will be use in a similar way as
the Entity/Relationship model.
3 SUBSTITUTION LOGIC
In this paper we select Substitution Logic
SL
F D
(Cordero et al., 2002a) to be the heart of
A/D CASE: A NEW HEART FOR FD3
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