This document presents an overview of entity relationship (ER) modeling. It defines key concepts of ER modeling including entities, attributes, and relationships. It discusses the main components of an ER model including strong and weak entities, simple and composite attributes, single and multi-valued attributes, stored and derived attributes, and null attributes. Examples are provided to illustrate these concepts such as an entity representing students with attributes like name, class, and roll number. The document was submitted by Saloni Rajput, a BSc V semester computer science student, to their professor C.L. Malviya.

1. Presented By
NAME : KAYAMAKHAN,SALONI RAJPUT
CLASS : BSC V SEM (CS)
COLLEGE : RAI SAHEB BHANWAR
SINGH COLLEGE
NASRULLAGANJ
SUBMITTED TO: C.L. MALVIYA SIR
RAI SAHEB BHANWAR SINGH COLLEGE
NASRULLAGANJ
1
Rai Saheb Bhanwar Singh College
Nasrullaganj

3. Definition:- Graphical Representation Of Entity Or
Attribute Is Called E R Model
Comments of E R MODEL
Entity :- The Collection Of Attribute Is Called Entry
An Entity Is Represented By A Set Of Attributers
B.Sc Vth sem

4. Name Class Roll no Address
Neha XII 101 Sehoe
Pooja XII 102 Indore
Priya XII 103 bhopal
Two Type Of Entity
1. Strong Entity – An Entity Set That Has A Primary Key Is Called
Strong Entity

5. Figure – Strong Entity
2. Weak Entity – An Entity Set Which
May Not Have Sufficient Attributer To Form A Primary Key Is Termed As
Week Entity Set.
Figure – Weak Entity

6. 2. Attributes – Elements Of Entity Is Called Attributers
Types Of Attributes
1. Simple & Compo Site Attributes
2. Single Valued & Multivalve Attributer
3. Stared & Derived Attributes
4. Null Attributes

7. 1.Simple & Composite Attributes :- a simple attribute is an
attributes that can not be broken into smaller subparts
2.Single Valued & Multivalve Attributes-
Single valued attributer if it can have only one value
Multivalve attribute if it can have more than one value
3.Stared & Derived Attributed :-An attribute which is already
present as an attribute for an entity
An attribute which is derived from a stored attribute as it was
not present as an attribute from an entity
4. Null Attribute – an attribute that can have null value is an
null attribute

8. Employee
Name Class Mob no
Neha XII -
Priya XII -
Pooja XII -

9. E-r Model Notation

10. B.Sc Vth
Teacher
Name
ID
Roll no
Name
Mob No
Class
Figure – Structure Of ER Model
Sumitted To – C.L. Malviya Sir