Week 4

Entity Relationship Diagram (ERD/ER Model)


Notation Of ER Model

Element Of ER

Type of Attribute

Type Of Attributes And Its Defination

Cardanality Constraint
1: M    => one to many
M : 1   => many to one
M : M => many to many
1 : 1    => one to one

Relational Key
Enables us to link the tables together in a database for easier data access storage

Types Of Relational Keys