Transcript arwan.lecture.ub.ac.id

DATABASE & INFORMATION
MODELS
Presented By
Team Teaching
Data vs Information
• Data: Collection of letters, numbers or facts
• Information: Processed data that provides
value
What is Database ?
• A database is a repository of data, designed to
support efficient data storage, retrieval and
maintenance
• A database may be specialized to store binary
files, documents, images, videos, relational data,
multidimensional data, transactional data, analytic
data, or geographic data to name a few
• Data : stored in various forms, namely tabular,
hierarchical and graphical forms
What is a database management
system ?
• Database Management System (DBMS),
• Software system that manages databases
• the terms “Database”, “DBMS”, “data server”,
“database server” often used interchangeably to refer
to a DBMS
• Why do we need database software or a DBMS?
•
•
•
•
Security
Can handle many users with good performance
Allows for concurrency while keeping data consistent
Protects from disaster
The evolution of database
management systems
• In the 1960s, network and hierarchical systems such as
CODASYL and IMSTM
• A revolutionary paper by E.F. Codd, an IBM San Jose
Research Laboratory employee in 1970 The paper
titled “A relational model of data for large shared data
banks”
• The Structured Query Language (SQL) invented by IBM
in the early 1970's has been constantly improved
through the years
• Today many businesses need to exchange information,
and the eXtensible Markup Language (XML) is the
underlying technology that is used for this purpose
The evolution of database
management systems , Cont’d…
Introduction to information models
and data models
• An information model is an abstract, formal
representation of entities that includes their
properties, relationships and the operations
that can be performed on them
• Data model : mappings of the Information
Model
The difference between information
model and data model
• The main purpose of an Information Model is
to model managed objects at a conceptual
level, independent of any specific
implementations or protocols used to
transport the data
• Data Models, on the other hand, are defined
at a more concrete level and include many
details
Relationship between an Information
Model and a Data Model
Types of information models
•
•
•
•
•
•
•
•
•
Network (CODASYL): 1970’s
Hierarchical (IMS): late 1960’s and 1970’s
Relational: 1970’s and early 1980’s
Entity-Relationship: 1970’s
Extended Relational: 1980’s
Semantic: late 1970’s and 1980’s
Object-oriented: late 1980’s and early 1990’s
Object-relational: late 1980’s and early 1990’s
Semi-structured (XML): late 1990’s to the present
Network model
• In 1969, CODASYL (Committee on Data Systems
Languages) released its first specification about the
network data model
• This followed in 1971 and 1973 with specifications for
a record-at-a-time data manipulation language
Hierarchical model
•
•
•
The first hierarchical database management system was IMS
(Information Management System) released by IBM in 1968.
It was originally built as the database for the Apollo space
program to land the first humans on the moon.
IMS is a very robust database that is still in use today at many
companies worldwide
Relational model
• 1970’s and early 1980’s
• The relational data
model is simple and
elegant
• It has a solid
mathematic foundation
based on sets theory
and predicate calculus
and is the most used
data model for
databases today
Entity-Relationship model
• In the mid 1970’s,
Peter Chen
proposed the entityrelationship (E-R)
data model
• He proposed
thinking of a
database as a
collection of
instances of entities
Object-relational model
• The Object-Relational (OR) model is very
similar to the relational model
• treats every entity as an object (instance of a
class), and a relationship as an inheritance
Other data models
• The last decade has seen a substantial amount
of work on semi-structured, semantic and
object oriented data models
• XML is ideal to store semi-structured data
• Object oriented data models are popular in
universities, but have not been widely
accepted in the industry
THANKS FOR YOUR
ATTENTION