PARULINSTITUTEOF ENGINEERING &TECHNOLOGY

FACULTY OF ENGINEERING & TECHNOLOGY

PARULUNIVERSITY

Database Management System

Introduction And Application Of DBMS, File
Processing System And Its Limitations
Computer Science & Engineering
Nilesh Khodifad (Assistant Prof. PIET-CSE)
Outline
• Introduction of DBMS
• Applications of DBMS
• Advantages of DBMS
• File Processing System
• Three levels ANSI SPARC database system
• Data Abstraction in DBMS
• Mappings and data independence
• Database users and DBA
• Database system architecture
Basic Terms
What is Data?
Data
• Fact that can be recorded or stored.

• Data is raw, unorganized and isolated facts that need

to be processed to produce required information. It is
simple and apparently random and useless until it is What
is this?
organized.
• E.g. Person Name, Age, Gender and Weight etc.
Basic Terms
Then! What is Information?
• When data is processed, organized,
structured or presented in a given context
so as to make it useful, it is called
information.

• Data: Each student's test score is one piece

of data
• Information: The class’s average score or
the school's average score is the
information that can be concluded from the
given data.

• Eg. Table of students information.

Basic Terms
Metadata
• Metadata is data about data.
• Data such as table name, column name, data type, authorized user and user
access privileges for any table is called metadata for that table.

Faculty
Emp_Name Address Mobile_No Subject
Prof. Ajay Shah Rajkot 9876543210 PPS

Metadata of above table is:

Table name such as Faculty
Column name such as Emp_Name, Address, Mobile_No, Subject
Datatype such as Varchar, Decimal
Access privileges such as Read, Write (Update)
Basic Terms
Data dictionary
A data dictionary is an information repository which contains metadata.
• Table Name – Faculty
• Column Name – EmpName, Address, Mob, Subject,
Salary
• Datatype – Varchar, Decimal
• Access Privileges – Read, Write (Update)
Data warehouse
A data warehouse is an information repository which stores data.
Faculty
Emp_Name Address Mobile_No Subject

Prof. Ajay Shah Rajkot 9876543210 PPS

Prof. Ajay Patel Surat 0123456789 DBMS
Basic Terms
Field
A field is a character or group of characters that have a specific meaning.
E.g, the value of Emp_Name, Address, Mobile_No etc are all fields of Faculty table.

Faculty
Emp_Name Address Mobile_No Subject
Prof. Ajay Shah Rajkot 9876543210 PPS
Prof. Ajay Patel Surat 0123456789 DBMS

Fields

Prof. Ajay Shah Rajkot 9876543210

Basic Terms
Record / Tuple
A record is a collection of logically related fields.
E.g, the collection of fields (Emp_Name, Address, Mobile_No, Subject) forms a
record for the Faculty.
Faculty
Emp_Name Address Mobile_No Subject
Prof. Ajay Shah Rajkot 9876543210 PPS
Prof. Ajay Patel Surat 0123456789 DBMS

Prof. Ajay Shah Rajkot 9876543210 PPS Record /

Prof. Ajay Patel Surat 0123456789 DBMS Tuple
Introduction
Some important terms to know :
Database
•A Database is a collection of inter-related (logically-related) data.
•E.g. Books Database in Library, Student Database in University etc.
Management
Manipulation, Searching and Security of data
e.g. Viewing result in GTU website, Searching exam papers in GTU website etc.
System
Programs or tools used to manage database
e.g. SQL Server Studio Express, Oracle etc.
DBMS
A Database Management System is a software for creating and managing databases.
Database Management System (DBMS) is a software designed to define, manipulate, retrieve
and manage data in a database.
e.g. MS SQL Server, Oracle, My SQL, SQLite, MongoDB etc.
Applications of DBMS
• DBMS is a computerized record-keeping system.
• DBMS is required where ever data need to be stored.
❑ E-Commerce (Flikart, Amazon, Shopclues, eBay etc...)
❑ Online Television Streaming (Hotstar, Amazon Prime etc...)
❑ Social Media (WhatsApp, Facebook, Twitter, LinkedIn etc...)
❑ Banking & Insurance
❑ Airline & Railway
❑ Universities and Colleges/Schools
❑ Library Management System
❑ Human Resource Department
❑ Hospitals and Medical Stores
❑ Government Organizations
• Advantages of DBMS

i. Reduce data redundancy (duplication)

Avoids unnecessary duplication of data by storing data centrally.
ii. Remove data inconsistency
By eliminating redundancy, data inconsistency can be removed.
iii. Data isolation
A user can easily retrieve proper data as per his/her requirement.
iv. Guaranteed atomicity
Either transaction executes 0% or 100%.
v. Allow implementing integrity constraints
Business rules can be implemented such as do not allow to store amount
less than Rs. 0 in balance.
vi. Sharing of data among multiple users
More than one users can access same data at the same time.
• Advantages of DBMS

vii. Restricting unauthorized access to data

A user can only access data which is authorized to him/her.
viii. Providing backup and recovery services
Can take a regular auto or manual backup and use it to restore the
database if it corrupts.
1. Reduce data redundancy (duplication)
Remove data inconsistency
Data isolation
• Data are scattered in various files. File - 1
• Files may be in different formats. Emp_Name Address Mobile Subject
• Difficult to retrieve the appropriate
data. Prof. Ajay Shah Rajkot 1234 PPS

DBMS allow us to access (retrieve) File - 2

appropriate data easily. Emp_Name Post Salary Load

• Data isolation is a property that Lecture

Prof. Ajay Shah 50,000 15
r
determines when and how
changes made by one operation File - 3
become visible to other Rat
concurrent users and systems. Emp_Name Teaching Knowledge
ing
• This issue occurs in a
concurrency situation. Prof. Ajay Shah Good Excellent 9
Guaranteed atomicity
Allow to implement integrity constraints
Sharing of data among multiple users
Want to
access
Computer Civil

Emp_Name Address Mobile Subject Addres Mobil

Emp_Name Subject
s e
Prof. Ajay Shah Rajkot 1234 PPS Prof. Ajay
Rajkot 1234 PPS
Shah
Want to Database management system
access allows more than one user to
access same data
simultaneously.
Emp_Name Address Mobile Subject Emp_Name Address Mobile Subject
Prof. Ajay Shah Rajkot 1234 PPS Prof. Ajay Shah Rajkot 1234 PPS
Electrical Mechanical
Restricting unauthorized access to data
File - 1
Emp_Name Address Mobile Subject
Wants to
Prof. Ajay Shah Rajkot 1234 PPS access
Faculty
File - 2 of other
college
Emp_Name Post Salary Load

Lecture Wants to
Prof. Ajay Shah 50,000 15 access
r Darsha
n
File - 3
Emp_Name Teaching Knowledge Rating Faculty

Prof. Ajay Shah Good Excellent 9

DBMS prevents unauthorized user to access
data.
Providing backup and recovery services

Provides facilities to backup and restore the database in case of

failure.
File Processing System and its limitations
File Processing System
File System
•File system is basically a way of arranging the files in a storage medium like hard disk. File
system organizes the files and helps in retrieval of files when they are required.
•File systems consists of different files which are grouped into directories. The directories
further contain other folders and files.
•File system performs basic operations like management, file naming, giving access rules etc.
•Example: NTFS(New Technology File System), EXT(Extended File System).
•A file system is a software that manages and organizes the files in a storage
medium, whereas DBMS is a software application that is used for accessing,
creating, and managing databases.
•The file system doesn't have a crash recovery mechanism on the other
hand, DBMS provides a crash recovery mechanism.
• File Processing Approach
-Each user maintains separate files—and programs to manipulate these files—because each
requires some data not available from the other user's files.

-This redundancy in defining and storing data results in wasted storage space and in
redundant efforts to maintain common up-to-date data

-In traditional file processing, data definition is typically part of the application programs
themselves; hence, these programs are constrained to work with only one specific database,
whose structure is declared in the application programs
• Database Approach
-A single repository maintains data that is
defined once and then accessed by various users
repeatedly through queries, transactions, and
application programs

When an organization uses the database

approach, many programs and users
share the data in the database. The
database does secure its data, however,
so that only authorized users can access
certain data items. While a user is
working with the database, the DBMS
resides in the memory of the computer.
DBMS vs. File System
File system is a software that manages and
DBMS is a software for managing the
1. organizes the files in a storage medium within
database.
a computer.
Redundant data can be present in a file
2. In DBMS there is no redundant data.
system.
It doesn’t provide backup and recovery of It provides backup and recovery of data even
3.
data if it is lost. if it is lost.
There is no efficient query processing in file
4. Efficient query processing is there in DBMS.
system.
There is more data consistency because of
5. There is less data consistency in file system.
the process of normalization.
It has more complexity in handling as
6. It is less complex as compared to DBMS.
compared to file system.
File systems provide less security in DBMS has more security mechanisms as
7.
comparison to DBMS. compared to file system.
Limitations of the File Processing System
➢ Separated and Isolated Data
➢ Duplication of data
➢ Data Dependence
➢ Difficulty in representing data from the user’s view
➢ Data Inflexibility
➢ Incompatible file formats
➢ Data Security
➢ Transactional Problems
➢ Concurrency problems
➢ Poor data modeling of real world
Thank You!!!
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