Entity Relationship Diagram (ER- Diagram)

Introduction

ER-Diagram is represents graphical representation of entities and relationship between them. ER-Diagram is really important for understanding flow of data within system.

Entity: An Entity is a business object which is represents a group of data.

ATTRIBUTE : An Attribute is a Sub-group of information/data within Entity.

Type of Entity Relationship:

• Many-to-Many Relationship
• One-to-Many Relationship
• One-to-One Relationship

SYMBOLS



EXAMPLE : ER-DIAGRAM