Matakuliah
Tahun
Versi
: M0174/OBJECT ORIENTED DATABASE
: 2005
: 1/0
Pertemuan 21
Object database design
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Learning Outcomes
Pada akhir pertemuan ini, diharapkan mahasiswa
akan mampu :
• Mahasiswa dapat Menunjukkan konsep
relational data model (C3)
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Outline Materi
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Why is UML important ?
Type
Classes
Two phase database design
Object database design
Entity relationship analysis
Top down
Bottom up
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Why is UML important ?
• In the past, the object oriented field has
been plagued by terminological
differences
• The confusion of terminology is a
consequence of the manner in which
object oriented technology has evolved
• The lack of a consensus terminology for
object oriented systems can be confusing
for the newcomer.
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Type
• Type refers to the interface specification
for objects of a certain kind
• Types may be classes or interfaces
• Implementation class refers to a type an
its implementation
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Classes
• Object oriented design normally refers
only to classes, since the aim is a plan
how to implement a design in a real
system
• The term type is not often used in object
oriented design material
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Two phase database design
• Database design proceeds in two stages:
Data Analysis – The purpose of this stage is
to model the part of the world relevant to the
database as a collection abstraction.
Data Design – the purpose of this stage is to
derive an implementation of the conceptual
model using the data model supported by the
DBMS that is to be used.
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Two phase database design
Universe of discourse
Real word phenomena, people,
place, things,….
Data Analysis
Conceptual model
Abstractions of type of real world
Phenomena: entities, attributes,
relationship
Data design
Logical model
Database representations of information:
Classes, types,….
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Two phase database design
• When a RDBMS is used, a further database
design phase is normalization, whereby the
logical model is refined so as to remove any
unnecessary duplication of data.
• The data model used for representing the
conceptual model is of a type called a semantic
data model.
• Semantic data model represent the meaning of
data using different abstraction for different
types of real world phenomena
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Object database design
• The object data model has sufficient
expressiveness to implement semantic
data models directly.
• Specifically, the object data model
explicitly supports the three main types of
abstractions also supported in the entity
relationship model entities (as classes),
relationships, and attributes
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Object database design
• at the time of database object design,
there is a dimension of design additional
which must be done by that is object
behavior design.
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Entity relationship analysis
• Objects within the object data model
represent entities, and the state of those
objects represents the facts about those
entities.
• There are two main approach to data
analysis:
Top Down
Bottom Up
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Top Down
• Top down can be thought of as working
from the general to the specific
• Example
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Bottom Up
• Bottom up can be thought of as working
from the specific to the general
• Example
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SUMMARY
• The UML provides a diagrammatic
language for representing analyses and
design for object oriented systems in
general and can be used in object
database design
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