The document outlines the fundamentals of Database Management Systems (DBMS), describing its functionality, characteristics, and advantages. It covers key concepts such as data abstraction, program-data independence, and multiuser processing, along with the roles of various database users. The DBMS revolutionizes data management by ensuring efficient storage, access control, and minimizing redundancy.

1. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Affiliated to Institution of G.G.S.IP.U, Delhi
BCA
DBMS
BCA 108
DBMS Basics
Keywords: Data, Database,DBMS

2. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Database Management System
(DBMS)
• Database Management System (DBMS): A
software system used to create and maintain
database.
• Database System: The DBMS software having
data . Sometimes, the applications are also
included.

3. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
DBMS Functionality
• Define a database : in terms of data types,
structures and constraints
• Construct or Load the Database on a
secondary storage medium
• Manipulating the database : querying,
generating reports, insertions, deletions and
modifications to its content
• Concurrent Processing and Sharing by a set of
users and programs – yet, keeping all data
valid and consistent

4. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Main Characteristics of the Database
Approach
• Self-describing nature of a database system: A
DBMS catalog stores the description of the
database. The description is called meta-data).
This allows the DBMS software to work with
different databases.
• Insulation between programs and data: Called
program-data independence. Allows changing
data storage structures and operations without
having to change the DBMS access programs.

5. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Main Characteristics of the Database
Approach
• Data Abstraction: A data model is used to
hide storage details and present the users
with a conceptual view of the database.
• Support of multiple views of the data: Each
user may see a different view of the
database, which describes only the data of
interest to that user.
• Sharing of data and multiuser transaction
processing :

6. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Instances and Schemas
• Schema – overall description of the database
• ex: cust_id : string;
cust_name : string;
cust_street : string;
cust_city : string;
• 2 Types of schema :
– Physical schema: database design at the physical level
– Logical schema: database design at the logical level
• Instance – the actual content of the database at a
particular point in time

7. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Data independence
• Physical Data Independence – the ability to
modify the physical schema without changing
the logical schema
• Logical Data Independence- the ability to
modify the logical schema without changing
the external view

8. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
The Entity-Relationship Model
• It is collection of entities and relationships
– Entity: real life “object” in the enterprise
– Relationship: an association among several
entities

9. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Database Users
Actors on the scene
– Database administrators(DBA): responsible for
authorizing access to the database, for co-ordinating
and monitoring its use.
• Casual : access database occasionally when needed
• Naïve or Parametric : they know little about Dbms and
databases.
• Sophisticated : these include business analysts,
scientists, engineers, others thoroughly familiar with
the system capabilities..

10. TRINITY INSTITUTE OF PROFESSIONAL STUDIES
Sector – 9, Dwarka Institutional Area, New Delhi-75
Advantages of Using the Database
Approach
• Controlling redundancy in data storage and in
development and maintenence efforts.
• Sharing of data among multiple users.
• Restricting unauthorized access to data.
• Providing persistent storage for program
Objects (in Object-oriented DBMS’s –
• Providing Storage Structures for efficient
Query Processing