Introduction to Computer and
Programming
CS-101
Lecture 6
Databases
By :
Lecturer : Omer Salih Dawood
Department of Computer Science
College of Arts and Science
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Operating System basic, purpose
type, PC operating system, DOS,
Windows, Linux.
Week 6
Mr. Mohammed Rahmath
Content
Data.
Data Organization.
Real-Time and batch Processing.
Database.
DBMS.
Common data models.
Types of Databases.
Database Uses and Issues.
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Operating System
Mr. Mohammed Rahmath
Operating System
Definition: An operating system is the interface
between the user and the architecture.
User Application
Operating System
Hardware
Mr. Mohammed Rahmath
Types of Operating Systems
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Batch operating system
Time-sharing operating systems
Distributed operating System
Network operating System
Real Time operating System
Mr. Mohammed Rahmath
Functions of Operating System
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Memory Management
Processor Management
Device Management
File Management
Security
Control over system performance
Job accounting
Error detecting aids
Coordination between other software and users
Mr. Mohammed Rahmath
Operating System - Properties
1. Batch processing
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Operating System - Properties
2. Multitasking
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Operating System - Properties
3. Multiprogramming
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Spooling
Definition: Spooling is an acronym for
simultaneous peripheral operations on line.
Spooling refers to putting data of various I/O
jobs in a buffer. This buffer is a special area in
memory or hard disk which is accessible to I/O
devices
Mr. Mohammed Rahmath
Disk Operating System(DOS)
• DOS refers to any operating system that runs
from a disk drive. Today, all operating systems
can be considered disk operating systems.
Mr. Mohammed Rahmath
Basic Commands of DOS
Mr. Mohammed Rahmath
Linux OS VS Windows OS
Topic
Linux
Windows
Price
Free Operating System
Paid Operating System
Ease
Not so Easy to use
More Easy to use
Reliability
More Reliable
Less Reliable
Software
Not so supportive for
most Software
All most all software
support windows OS
Software Cost
Open source mostly
Paid Software
Do not much Hardware
Most of the hardware
supportive
Highly Secure
Not so highly Secure
Hardware
Security
Mr. Mohammed Rahmath
Abbreviations
DB : Database.
DBMS : DataBase Management System.
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Data
Data are values of qualitative or quantitative
variables, belonging to a set of items.
Data can includes:
Facts or comments about people, places,
things, and events
Audio, photographs, and video
Two ways to view data:
Physical view
Logical view
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Data Organization
 Character
Field
Record
File
Table
Database (DB)
Key Field
Batch Processing Versus Real-Time
Processing.
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Key Field
Unique identifier also known as primary field
Common examples of primary key:
Social Security Number
Student Identification Numbers
Employee Identification Numbers
Part Numbers
Inventory Numbers
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Real-Time and batch Processing
Batch processing :
Data is collected over a period of time and the
processing happens later all at one time.
Real-time processing :
Also known as online processing because it
happens immediately during the transaction
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Databases
• Collection of integrated data Logically related
files and records.
• Databases address data redundancy and data
integrity.
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Needs for DB
Sharing
Security
Less data redundancy
Data integrity
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Database Management
Are specially designed applications that interact
with the user, other applications, and the
database itself to capture and analyze data.
Database Management System(DBMS) engine.
Data definition subsystem
Data manipulation subsystem
Application generation subsystem
Data administration subsystem
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DBMS
DBMS programs are designed to work with
data that is logically structured or arranged.
Data models define rules and standards for
data in a database.
Five common data models :
• Hierarchical database
• Network database
• Relational database
• Multidimensional database.
• Object-oriented database.
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Hierarchical Database
Fields or records are structured in nodes
Nodes are points connected like branches
One parent per node; a parent has several
child nodes (one-to-many relationship)
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Network Database
Hierarchical node arrangement
Each child node may have more than one
parent node (many-to-many relationship)
Additional nodes are called pointers
Nodes can be reached through multiple paths
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Relational Database
 Data stored in table called a relation
Tables consist of rows and columns
Tables related via a common data item
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Multidimensional Database
 A variation and an extension of the relational
model to include additional dimensions,
sometimes called a data cube.
Good for representing complex relationships
Advantages of Multidimensional Database:
Conceptualization.
Processing speed.
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Object-Oriented Database
 Works with unstructured data
Photographs
Audio(reviewed)
Video
Objects contain both
data and instructions
Organize using objects,
classes, entities,
attributes, and methods
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Types of Databases
 Individual
Company or shared
Distributed
Commercial
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Individual Databases
 Also called a microcomputer database
Integrated file collection for one person
usually under the person’s direct control
Generally stored on the user’s hard-disk drive
or on a LAN file server.
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Company or Shared Databases
 Usually stored on a central database server
and managed by a database administrator
Users throughout a company can access the
database through the company’s networks
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Distributed Databases
 Database is located in a place or places other
than where users are located
Typically, database servers on a client/server
network provide the link between users and the
distant data.
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Commercial Databases
 Generally an enormous database developed by
an organization to cover particular subjects
Access is offered to the public
or selected outside individuals
for a fee
Most commercial databases are designed for
organizational and individual use
Also referred to as information utilities or data
banks
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Database Uses and Issues
Strategic uses
Special type of database called data
warehouse.
Data mining is used to search databases for
information and patterns
Security
Databases are valuable.
Protection necessary.
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Database Careers
Database administrators
Determine the most efficient ways to
organize and access a company’s data
Responsible for database security and
backing up the system
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Thank you for your attention
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Lecturer : Aasd Abd Elrashid