3. CONTENT IN PRESENTATION
Introduction to Database Management System
DBMS v/s File System
Database models
Database Languages: DML, DDL
Database users and administrators
Applications of DBMS
Advantage and Disadvantages of DBMS
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4. INTRODUCTION TO DBMS
Database
is collection of related data and its metadata organized in a
structured format for optimized information management.
Database Management System (DBMS)
is a software that enables easy creation, access, and
modification of databases
for efficient and effective database management
Database System
is an integrated system of hardware, software, people,
procedures, and data
that define and regulate the collection, storage, management,
and use of data within a database environment
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6. Bases DBMS Flat file system
Definition
Data
redundancy
Cost
Use
Securit
y
DBMS is a collection of interrelated data
and software programs to access those
data.
There is no problem of data
redundancy.
DBMS software are very costly and
also regular update makes it costly.
Mostly, large organizations use
DBMS who can afford it and have a
large number of client and employees
to be managed.
Views are created and an employees
can’t see all information available,
hence there is security.
Flat file system stores data in a plain
text file. Here, the records are
specified in a single line.
There is main problem of data
redundancy.
Flat file are cost
effective.
Small organizations use it as it is
cost effective and who have to deal
with small number of clients and
employees.
Any information can be seen by
anyone, hence there is no
security.
DBMS VS FLAT FILE
SYSTEM 6
8. • The basic design or the structure of the database is the
data model.
• It is a collection of conceptual tools for describing
data, data relationships, data semantics, and
consistency constraints.
• The basic structure of the database that organizes data,
defines how the data are stored and accessed, and the
relationships between the data, is the data model.
DATABASE MODEL
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9. TYPES OF DATABASE MODELS
o Hierarchical Model
o Network Model
o Relational Model
o E-R Diagram
o Object-Oriented Model
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10. o Records are organized into a hierarchy of relationships.
o Data is represented as a tree rather then graphs.
o A record type can belong to only one owner type but a
owner type can belong to many record type so that it
established one to many relationship.
o Top record is known as root record and all the records
keep parent child relationship.
HIERARCHICAL DATA MODEL
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11. • It is modified version of Hierarchical Data Model where it
replace the hierarchical tree with a graph thus allowing more
general connections among the nodes.
• They are difficult to use but are more flexible than
hierarchical databases.
• Ability to handle many-to-many relationships.
NETWORK DATA MODEL
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12. Agent Code Name Customer code
A-101 Ramesh C- 11
A-102 Kriti C- 10
A-103 Laxmi C- 12
Student
RELATIONAL MODEL
It store the data in form of two-dimensional table
( i.e row & columns). It is more powerful because they
require few assumptions on how data would be related
and how data would be extracted.
A single database can be spread across several tables.
Some well known RDBMS:
IBM DB2, Informix, Microsoft SQL Server etc.
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13. E-R DIAGRAM: CROW’S FOOT
MODEL
Entity
represented by a rectangle with
its name in capital letters.
Relationships
represented by an active or
passive verb that connects the
related entities.
Connectivities
indicated by symbols next to
entities.
2 vertical lines for 1
“crow’s foot” for M
S511 Session 2, IU-SLIS 13
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14. OBJECT-ORIENTED MODEL
The data is stored in the form of objects, which are
structures called classes that display the data within.
The object oriented structure has the ability to handle
graphics, pictures, voice and text, types of data,
without difficultly unlike the other database
structures. This structure is popular for multimedia
Web-based applications. It was designed to work with
object-oriented programming languages such as Java.
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15. Data Definition Language(DDL):
o Database language that is used to create, delete or modify
database schema is called DDL.
o It is used by Database Administrators(DBA) to specify the
conceptual schema.
o DDL interpreter converts DDL statements into equivalent
low level statements understood by the DBMS.
o Normally, create, alter, and drop statements are DDL
statements.
o DDL statements make changes in the schema
DATABASE LANGUAGES
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16. dExample: For Create comman
create table Student
(
snd char(4),
sname saini (50), standard
integer
);
Example: For Drop command
drop Student;
Example: For Alter command alter
table Student
ADD COLUMN address varchar(20)
;
EXAMPLE OF DDL
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17. • Database language that enables insert, update, delete,
and retrieval of data from the database is called Data
Manipulation Language.
• DML complier converts DML statements into equivalent
low level statements that the database understands.
• Normally, select, insert, update, delete are DML
commands.
• DML reflects change in the instance, not the schema.
DML( DATA MANIPULATION
LANGUAGE)
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19. DBA is a person who has control over data and the
associated application programs. He is the one who can
define schema, install new software, enforcing security
to the system, etc.
Major responsibilities of DBA are:
1.Define schema and modify as per needed
2.Install new software for efficient operations
3.Enforcing and monitoring security
4.Analyzing the data stored in the DBMS
5.Keeping the backup of the DBMS periodically
6.Ensuring the state of the hardware and software
DATABASE ADMINISTRATORS
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20. APPLICATIONS OF DBMS
Airlines and railways
Banking
Education
Telecommunication
Government
Private organisations
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21. ADVANTAGE OF DBMS
Improved data sharing
Improved data security
Improved data integrity
Minimized data inconsistency
Reduced Redundancy
Better administration and control
Better transaction management
Data independence
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22. DISADVANTAGE OF DBMS
Increased costs
Management complexity
Frequent upgrade
Insufficient database expertise
Data security and integrity
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End user data – raw facts of interests to the end user
Metadata – description of data characteristics and relationships
Organization of data helps:
improve data accuracy
improve timely access
correlation and comparison
DBMS: a collection of programs that manages the database structure, control access to data
- Makes data management more efficient and effective
- Query language allows quick answers to ad hoc queries
- Provides better access to more and better-managed data
- Promotes integrated view of organization’s operations
- Reduces the probability of inconsistent data