BUSINESS DEVELOPMENT WITH
INFORMATION SYSTEMS
FORRETNINGSUDVIKLING MED
INFORMATIONSSYSTEMER
LECTURE 7 – MODELLING OF DATA AND INFORMATION
FORELÆSNING 7 – MODELLERING AF DATA OG INFORMATION
Entity-Relation Diagram (ERD)
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
LEARNING GOAL FROM COURSE DESCRIPTION
The objective of the course is that the students, after having participated in the course ‘Business
Development with Information Systems (IS)’ are able to:
 apply the concepts of system, information and model when discussing business processes and
their related information systems
 explain the concept of an information system and its components


analyse t h e i m p a c t on b u s i n e s s p rocesses a n d b e c a p a b l e of a n a l y s i n g t h e e l e m e n t s of s u c h a s y s t e m
apply modelling techniques to identify processes, working procedures and data structures for
analyzing and improving business processes and hence the underlying information systems

describe how informat ion s y s t e m s c a n b e u s e d to creat e b u s i n e s s a d v a n t a g e s for a c o m p a n y , i.e. to iden t ify, a n a l y s e a n d e v a l u a t e IT opportunities b y m e a n s of m o d e l s s u c h
a s Porters Five Forces, Valu e Ch ain s, a n d Competitive S t r a t e g i e s a n d Prioritization Matrices

analyse a n d describe operation al ap p licat ion s of informat ion s y s t e m s s u c h a s Enterprise Resource P l a n n i n g s y s t e m s , Social B u s i n e s s S y s t e m s , CRM, SCM, Electronic
c o m m e r c e a n d decision support s y s t e m s b y m e a n s of m o d e l s from t h e literature

evaluate t h e m a n a g e r i a l c h a l l e n g e s in relation to I S a n d t h u s b e c a p a b l e of analysing relation sh ip s con cern in g t h e role of IS in b u s i n e s s a s well a s a p p l y b a s i c project
m a n a g e m e n t tools s u c h a s e . g . Gantt Chart

produce a n d present a n a l y t i c a l results from t h e a b o v e m e n t i o n e d m e t h o d s a n d tools u s i n g a scient ific, con cise, correct a n d c a p t i v a t i n g l a n g u a g e

reflect on one's own a s well a s the group's work on the project
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
MODELLING
SEPTEMBER 2016
Klaus Vilstrup Pedersen
External Lecturer
UML CD
ERD
ERD
Technology independent
ERD
Technology dependent:
e.g. Relationel Model
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
MODEL THE ”WORLD”


We want to create a virtual world (IT-system) that is one-to-one with the
(future) physical world.
 The physical world has a structure
 An event in the real world might have an effect on our virtual
world
We want to model the “world” that is in scope:
 Model the Entities we want to manage
 Model the data (Attributes) we need for our purpose
 Model the Relationships between the Entities is scope
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
WHY DATA MODELLING?
Organizations need to understand the structure and flow of data
Data models facilitate clarification of …
the data the systems need to store and
manage
the most efficient way of organizing the data
potential risks and challenges related to data within the
organization
Think about how many systems of our everyday-life that depends on
data: banking, traffic, social networks…

OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
DATA MODELLING PROCESS
Identify
entities
and
attributes
Choose
unique
identification
Model the
relationships
Decide on
business
rules
Review the
model
Example: Student administration system
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
ENTITY RELATION DIAGRAM (ERD)
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
UML CD
ERD
ERD
Technology independent
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
ENTITIES AND ATTRIBUTES (INCL. IDENTITY)
Something that has identity and properties
 Lecturer, Car, Location, Chair, Organizational unit, …….

Entity type
Template for Student instances
Entity instances
Template for Student instances




213
Charlie George
Wingstreet 4
12.12.2000
Students
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
ENTITY TYPE AND -INSTANCE

Entities have attributes, which are characteristics that are
important to the system e.g. a customers name, phone number,
product name, price etc.
Attribute t y p e s
( d e f i n e s t h e d a t a type)
I n s ta nce
(concrete v a l u e )
Firstname
Anders
Lastname
Sand
Address
P a r a d i s æ b l e ve j 1 1 1
Star tDate
01 -0 8 -2 0 1 4
SchoolName
Aarhus University
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
EXERCISE

Which attributes would make sense for the entity ’Customer’ in a
business selling cars.
Siblings
Household
First name
City
Birthplace
Favourite dish
E-mail
Last name
Adress
Preferences
Telephone no.
Supplier
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
IDENTITY
Every entity must have an identity i.e. in ERD a primary key
 The primary key is an attribute or combination of attributes that
uniquely identify an instance of the entity
 In other words, no two instances of an entity may have the same
value for the primary key

Why do we n e e d ”artificial” keys – e . g . StudentID?
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
EXERCISE
Create a list of Entities in the “student administration” domain
 Add Identity
 Add relevant attributes

OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
RELATIONS

Entities can be in a relationships with each other: Entity
Relationships
Diagram
› E.g. A Customer places an Order or a Student attend a School
› Relationships are modeled by straight lines between entities
Attends
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
CARDINALITIES
Rule 1 : One ADVISOR c a n b e related
to m a n y STUDENTS
Rule 2 : One STUDENT c a n b e
related to only o n e ADVISOR
It is a 1 : n
relationship
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
CARDINALITIES
Important:
• Business logic/rules
drives the model
• It is NOT the model
that defines the
business logic/rules
The model is simply one
way of expressing business
logic/rules
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
CARDINALITIES
Expressed by a maximum cardinality:
Student
Study
Add a minimum cardinality to enhance the precision:
Student
Study
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
EXERCISE

Group
Students
To which ERD does the
instance drawing belong
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
EXERCISE

Group
Students
To which ERD does the
instance drawing belong
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
EXERCISE

Course
Students
To which ERD does the
instance drawing belong
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
EXERCISE
For the ERD of the “student administration” domain:
 Create Relations between Entities
 Decide on Cardinalities
 Check the model i.e. READ THE MODEL!!!!!!

OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
OTHER INFORMATION MODELLING NOTATIONS
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
RELATIONEL MODEL
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
ERD
Technology dependent:
e.g. Relationel Model
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
ENTITY TO RELATIONEL
Table
Primary Key
Attributes
Person
Records
Name
Id
Street
No
City
Knud La rs e n
1
H av n e g a d e
1
Aarhus
H a n n e Nielsen
2
Vejlevej
21
Viborg
J a n La rs e n
3
H av n eve j
1
Aarhus
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
RELATIONSHIPS TO RELATIONEL
Foreign Key
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
DEALING WITH MANY TO MANY
S o u rce: Sixhøi, C. & B r a nd t, C. J. ( 2 0 2 0 ) . Modelling Compendium v2.0: Business Development with Information S y s t e m s . Aarhus B S S .
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
WORKSHOP A – BPMN – REEV CASE
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
ReEV case- AS-IS (not the reality!)
ReEV case- AS-IS (With swimlanes)
REEV case – TO-BE
Create a
subprocess
for this part
Q&A BUSINESS PROCESS MODELLING NOTATION (BPMN)

Question
#
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
Modelling
OCTOBER 2022
Klaus Vilstrup Pedersen
External Lecturer
DEPARTMENT OF MANAGEMENT
AARHUS UNIVERSITY