Chapter 4, Problem 7RQ

a)

Program Plan Intro

Graphical representation of ERM (Entity Relationship Model) entity component:

Crow’s Foot entity box for “Student”

b)

Program Plan Intro

Graphical representation of ERM cardinality component:

The following table illustrates the different connectivity and participation combinations which are maintained by the Crow’s Foot notation:

Crow’s Foot cardinality notation

Notation	Cardinality	Description
	(0,N)	Zero or more instances
	(1,N)	One or more instances
	(1,1)	One instance
	(0,1)	Zero or one instance

c)

Program Plan Intro

Graphical representation of ERM entity component:

Crow’s Foot weak relationship symbol

d)

Program Plan Intro

Graphical representation of ERM entity component:

Crow’s Foot strong relationship symbol