Transcript Judul - Binus Repository

Matakuliah
Tahun
Versi
: M0174/OBJECT ORIENTED DATABASE
: 2005
: 1/0
Pertemuan 1
Database Approach
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Learning Outcomes
Pada akhir pertemuan ini, diharapkan mahasiswa
akan mampu :
• Mahasiswa dapat Menjelaskan penerapan
penggunaan dan konsep data model dari
generasi teknologi database (C2)
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Outline Materi
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The Organization
Data and information
An organization's database
File oriented system vs dbms
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The Organization
• A database system exists to provide an
organization with the information system
necessary for it to carry out its activities.
• An organization is a very general term
which refers to “any organized body or
system or society”, and the database
approach is applicable to organizations in
general
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Data and information
• What is data ?
• What is information ?
• Examples
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An organization's database
• Computer program are used to assist
people to carry out many of the activities
that enable organization of all type to
operate effectively
• To do this these application program will
usually have to access stored information
about organization and environments
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An organization's database
• Information about organization and
environments is usually represented within
computer as data which is stored as data
file on storage device.
• Database Management System(DBMS) is
a particular type of computer program
which is used by application program to
manage and provide access to the stored
data
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An organization's database
• The collection of data managed by a
DBMS is called a Database.
• Examples
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File oriented system vs dbms
• File-Oriented Systems
– The traditional (pre-database technology)
approach, database exist as a collection of
files
– Here we have file are recorded details of
information about organization and
environment
– The application program inputs data, check
the new data is valid, and updates appropriate
files.
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File oriented system vs dbms
• Two characteristic of file-oriented system
– Data files are organized for convenience of
specific programs.
– Programs must have built into them
knowledge of how files are organized, the
ways in which records can be accessed, and
the meaning of the data.
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File oriented system vs dbms
• That characteristic have two undesirable
consequences
– File-Oriented computer system are likely to be
unstable.
– Management of data can be difficult. Data
may be distributed across a number of files to
be accessed by different application programs
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File oriented system vs dbms
• Database Approach
– The database approach to computerizing
information activities is to treat the
organization data as a resource which is
shared by all relevant application program.
– The data is made shareable by structuring in
it such a way that it has the same structure as
the information that it represents
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File oriented system vs dbms
– Application programs can then be
programmed to access the logical structures
of the information that is processed, rather
than the structure of files that are used to
store the data that represent it
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File oriented system vs dbms
• The general objective of the database
approach: “A database should be a
natural representation of information as
data, with few imposed restrictions,
capable of use by all relevant
application without duplication.”
• The database approach is therefore
centered on data, rather than on the
process applied to the data
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File oriented system vs dbms
• A DBMS enables an organization to
implement the database approach. It does
this by supporting description of data, both
in term of how it is physically stored and in
term of the logical structure of the data
• The physical structure of the data is to do
with how the data is represented on
storage device. The logical structure of the
data is to do with how it appears to the
user of the database
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File oriented system vs dbms
• DBMS makes possible a natural
representation of data by shielding the
user from the physical data structures.
• The users sees only the data which is
structured in a way that models the
structure of the information it represents,
and not the ways in which it is stored.
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File oriented system vs dbms
• The description of the data structures are
called schemas.
• The database has two parts:
– Database intension which is the set of
schemas which define the structure of
database.
– Database extension which is the data values
themselves, contained in the database
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SUMMARY
• An organization can be viewed as a
system of activities coordinated by a flow
information.
• The conventional file-oriented approach is
to build computer systems to support
activities, or applications.
• The database approach is to treat the
database as an entity in its own right, and
to design it to model the organization.
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SUMMARY
• A special program called a database
management system (DBMS) is used to
manage and provide access to the
database.
• The database administrator (DBA) is
responsible for managing the database
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