Database Design
&
Management
Contents (Summary)
• Concepts of Database Management
• Database Designing and Modelling
• Client-Server Architecture, Data Dictionaries
• SQL
– DDL,DML,Views ,Constraints
• Oracle SQL
• Distributed Database
• Object oriented database
• Database Administration
Method of Delivery
• Text Books
• Reference Book/s
• Lecture Slides
• Lab work (SQL)
• Helping notes or Reference website
(email)
Key to success
• Punctuality
• Hard work
• Practice
• Devotion
• Dedication
Text Book
(1) Modern Database Management By:
Fred McFadden, Jeffrey Hoffer, Mary Prescott 12th Edition, Addison Wesley
(2) Database Systems Concepts By:
Silberschatz., Korth., Sudarshan 4th Edition
(3) Database Systems By:
Thomas Connolly, Carolyn Begg 3rd Edition
(4) An Introduction to Database Systems By:
C.J.Date
Lab Software
• Micro soft visio 2016
• Microsoft SQl
What is Data ?
Definition of Data
•Data consists of Facts, text, graphics,
images, sound and video segments that
have meaning to user’s environment.
•Data can exist in a variety of forms:
- As numbers or text on pieces of paper
- As bits and bytes stored in electronic
memory
- As facts stored in a person's mind.
Data Type
Data is what we measure
Data type refers to the classification of a
particular type of information
• integer
• floating point
• character, string
• date
• student record
• blob (binary large object)
Data in Context
Large volume of facts, difficult
to interpret or make decisions
based on
INFORMATION
• Data that has been
processed in such a way that
it can increase the
knowledge of person who
uses it
Useful information that managers can use for
decision making and interpretation
Data vs Information
• Data into information
–Summarise data
–Data In context (table)
–Decision support
• We use Database term without
distinguish data or information
ACTIVITY
• Please write down the data for cricket
match bowling
• Do you get any information??
Definition of Database
“ Database is a shared collection of logically
related data, designed to meet the information
needs of multiple users in an organization ”
Database is designed, built, and populated
with data for a specific purpose. It has an
intended group of users and preconceived
applications in which these users are
interested.
Alternative Terminology
D a ta P r o c e ssi n g T e r m s
F o rm a l T e rm s
A l te r n a ti v e 1
A l te r n a ti v e 2
R e l a ti o n
T a b le
F ile
T u p le
Row
R e co rd
A ttr i b u te
C o lu m n
F ie ld
• Formal terms are mostly used for technical users.
• Data processing terms are more natural for non
technical users.
Computerized File
Based Processing
System
Computerized File-based
Processing
File handling routines &
File definition
Sales files
Sales
File handling routines &
File definition
Contracts
Contracts files
File-based Systems
• A collection of application programs
that perform services for the end
users (e.g. reports).
• Each program defines and manages
its own data.
Three file processing systems
Duplicate
Data
Limitation of Computerized Filebased Approach
• Separation and Isolation of data
• Each application maintains its own set of data.
• Users of one application may be unaware of potentially
useful data held by other applications.
Duplication of data (data redundancy)
•
Same data is held by different files.
Limited Data Sharing
No centralized control of data
Lengthy Development Times
Programmers must design their own file formats
Excessive Program Maintenance
80% of information systems budget
Limitation of File-based
Approach
• Accessibility
• Data is stored using programs that are written in
different languages and format
• Cannot easily access other files due to incompatible file
format.
• No control over access and manipulation of data beyond
that imposed by application programs.
• Hard Coded Queries (Data dependence)
• File structure and all definition of data are defined in the
application program code.
• Programs are written to satisfy particular functions /
requirements.
• Any new requirement needs a new program.
Problems with Data Dependency
 Each application programmer must maintain
their own data
 Each application program needs to include
code for the metadata of each file
 Each application program must have its own
processing routines for reading, inserting,
updating and deleting data
 Lack of coordination and central control
 Non-standard file formats
Problems with Data
Redundancy
• Waste of space to have duplicate data
• Causes more maintenance headaches
• The biggest Problem:
– When data changes in one file, could
cause inconsistencies
– Compromises data integrity
SOLUTION:
Database Processing
System
Database Processing
Sales
Application
Sales
DBMS
Database
Contracts
Application
Contracts
The DATABASE Approach
• Central repository of shared data
• Data is managed by a controlling
agent
• Stored in a standardized,
convenient form
Requires a Database Management System (DBMS)
Database Management System
Application
#1
Application
#2
Application
#3
DBMS
DBMS manages data
resources like an operating
system manages hardware
resources
Database
containing
centralized
shared data
Database Management System
(DBMS)
A collection of programs that enables users to
define,create and maintain and control access to the
database.
General-purpose software system that facilitates the
processes of defining, constructing and
manipulating databases for various applications.
Defining
- specifying data types, structures, constraints.
Constructing - storing of data
Manipulation - querying, updating and reporting.
Popular DBMS In The Market
Sybase SQL Anywhere
Informix Dynamic Server
Borland Interbase
Database Management System
• A DBMS is a data storage and retrieval
system which permits data to be stored
non-redundantly while making it appear
to the user as if the data is wellintegrated.
Advantages of Database Approach
• Program-Data Independence
– Metadata stored in DBMS, so applications don’t need to
worry about data formats
– Data queries/updates managed by DBMS so programs
don’t need to process data access routines
Results in: increased application development and
maintenance productivity
• Minimal Data Redundancy
– Leads to increased data integrity/consistency
Advantages of Database Approach
• Improved Data Sharing
– Different users get different views of the data
• Enforcement of Standards
– All data access is done in the same way
• Improved Data Quality
– Constraints, data validation rules
• Better Data Accessibility/
Responsiveness
– Use of standard data query language
(SQL)
• Security, Backup/Recovery,
Concurrency
Costs and Risks of the
Database Approach
• Up-front costs:
– Installation Management Cost and
Complexity
– Conversion Costs
– Cost of DBMS
– Additional hardware costs.
Ongoing Costs:
– Requires New, Specialized Personnel
– Need for Explicit Backup and Recovery
– Higher impact of a failure
• Organizational Conflict:
– Old habits die hard
The Range of
Database Applications
• Personal Database – standalone desktop
database
• Workgroup Database – local area network
(<25 users)
• Department Database – local area
network (25-100 users)
• Enterprise Database – wide-area network
(hundreds or thousands of users)
Personal
Computer
Database
Workgroup database with local area network
An
enterprise
data
warehouse
Components of
DBMS Environment
1. Hardware
Can range from a PC to a network of computers.
2. Software
DBMS itself and operating system, including any
network software if network is being used.
3. Data
Includes actual data used by the organization, and
description of data (schema). Also a system
catalog contains data such as the names of
authorized users.
Components of
DBMS Environment
4. Procedures
Instructions and rules that should be applied to the
design and use of the database, and the use of
the DBMS.
5. People
Data & Database Administrator
Database Designer :- Logical & Physical
Application Programmers
End Users
DBMS Environment
Bridge
Data
Software
Hardware
Procedures
People
Machine
Human
Database System
Environment
Users/Programs
Application Programs/Queries
Software to Process
Queries/Programs
Software to Access Stored Data
Stored Database
Definition
Stored
Database
Evolution of DB Systems
• Flat files - 1960s - 1980s
• Hierarchical – 1970s - 1990s
• Network – 1970s - 1990s
• Relational – 1980s - present
• Object-oriented – 1990s - present
• Object-relational – 1990s - present
• Data warehousing – 1980s present
• Web-enabled – 1990s - present
Summary
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Course Contents
Data
Information
Data Vs Information
Database Terms
DBMS
Advantages
Disadvantages of DBMS
Database Terms
Comparison of Computerized File Based Processing
System & Database System