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A Company and its Data     7

                           Architecture (SOA) were carried out taking into account
                           legacy databases without restructuring them. Companies did
                           not have the means  nor the objective to  modify these
                                                       1
                           databases. The IT industry  has largely maintained the idea
                           that new technologies would be capable of offering a return
                           on investment without modifying the core of  existing
                           systems. Now, companies are realizing that these new
                           technologies have been oversold. It is now obvious but it was
                           not easy to convince people that, if data is no longer reliable,
                           then the software that use them are also no longer reliable,
                           whether they be oriented objects, BPM, SOA or others.

                              During the past few years, there has been a steady decline
                           in the quality of data and data modeling expertise is
                           becoming increasingly rare. It is more common to hire a Java
                           engineer than a UML data modeler. It is even present in
                           computer science training courses, surely a sign that  this
                           decline runs deep. And yet, in the first days of IT, a formal
                           approach to data existed. Procedures and methodology were
                           set in stone with :
                                            2
                               –  conceptual data modeling to present business
                           information in a format that can be understood by people
                           who are not technical specialists;

                               –  logical data modeling for the translation of conceptual
                           modeling to data structures that respect IT needs and
                           feasibility;

                               –  physical data modeling for the translation of logical
                           modeling into software, i.e. the “physical database schema”.






                           1. Software vendors, consulting groups, IT services companies, etc.
                           2. This terminology was incarnated in the MERISE methodology in
                           France, from the 1970s.  The same  levels appear in several English
                           language approaches that have been around for some time, in particular
                           the Zachman Framework from about the middle of the 1980s.
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