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PROOF
Data Modeling—Object-Oriented Data Model
Michalis Vazirgiannis
Athens University of Economics and Business
I. INTRODUCTION IV. CONCLUSION—RESEARCH ISSUES AND PERSPECTIVES
II. MOTIVATION AND THEORY V. CASE STUDY: OBJECT RELATIONAL SOLUTIONS FOR
III. INDUSTRIAL SYSTEMS—STANDARDS MULTIMEDIA DATABASES
GLOSSARY the framework of the program, the internal mech-
anism determines what specific name of different
data model In data modeling we try anize data purposes is known as function overloading.
so that they represent as closely as possible a real relational model A data modeling approach having
world situation, yet representation puters is found very essful industrial implementations
still feasible. A data model encapsulates in DBMS. The fundamental modeling constructs
three elements: objects’ structure, behavior and in- are the relations consisting of tuples of values each
tegrity constraints. one taking its semantics from an appropriate at-
tribute. The relations represent entities of the real
world and relationships among entities.
encapsulation A property of the object oriented model, promoting data and operation indepen-
dence. This is achieved by hiding the internal struc- I. INTRODUCTION
ture and implementation details from the external
world simplifying thus the maintenance and usage A. Need for Data Modeling
of a multitude of object classes in an application.
inheritance The ability of one class to inherit the The word “datum” comes from Latin and, literally in-
structure and behavior of its ancestor. Inheritance terpreted, means a fact. However, data do not always
allows an object to inherit a certain set of attributes correspond to concrete or actual facts. They may be
from another object while allowing the addition of imprecise or may describe things that have never hap-
specific features. pened (., an idea).
object-oriented modeling It is an abstraction of the re