Summary Business Modeling (lectures, web-lectures, reader)
DATA MODELING
Introduction to Management Information Systems
Business objectives for Information Systems
• Operational excellence
Information Systems can improve efficiency, which means more profit.
• New products, services, and commercial business models
Commercial business model describes how a company produces, delivers, and sells its
products and services.
• Customer and supplier intimacy
• Improved decision making
• Competitive advantage
• Survival
Information Systems: set of interrelated components that manage information to support an
organization in
- decision making and control
- problem analysis and creation of new products
plus their organizational, technological, and people context.
Components are realized using Information Technology (IT), e.g. Hardware and Software.
Data: raw facts and figures without meaning of their own
It needs to be processed by IS to become information (data in meaningful, useful form).
Data -> IS -> Information
Information Systems ≠ Information Technology (IT)
Introduction to Data Modeling
Functions of Information Systems
• Represent data about entities in the problem domain
• Present and manipulate represented data
We use models to map the complex reality of a business domain and simplify it. A model only
contains those things which are considered relevant for the information system to be developed.
Two general data models:
• Model of problem domain (designed by: interview users, looking at existing data/IS)
Clarify the understanding for a domain and is input in the design and development of an IS
• Model of IS representation
Entity = real world thing about which Information System
stores information
Relation = connection between entities
Attribute = property of entity (significant piece of data
containing values that describe each instance of that class)
Different entities can share the same attributes, but with different attributes values (different states).
,Problems: an IS needs to
- distinguish different states of same entity
- distinguish different entities with same state
Solution: each entity gets identifier (attribute or collection of attributes) which is unique and remains
constant over entity life time.
Entity type = abstraction of common structure of entities
It has attributes. Instances share those attributes.
Example: Patient with attributes: patient number, name, gender, date of birth.
In UML (Unified Modeling Language):
• An entity is called an object.
Object is tangible (physical, like patients, cards) or intangible (conceptual, like diagnoses).
Existing objects from a class form its population.
• An object has attributes which have values – value of an attribute may change over time.
• Link = relationship between two or more objects (representing by a line which connects the
objects and a short description)
• An entity/object type is called an class – classifies all objects of a certain type and is visualized
as a rectangle that is labeled with the name of this class, this name has to be unique within
the diagram.
You get in trouble, if there is another patient whose name is also Stef van Bracht, because you use the
names of patients to identify the patient objects, better is a number as identifier, this is unique.
➔ Object identifiers (OID) are attributes of objects that ensure that they can be identified
among all other objects.
Association = relation between classes (link is instance of association)
Add short description by the line
Read it from left to right; exception -> when arrow pointing in other direction (inverse)
Population of an association is the set of all corresponding links that are instances of this association
at a certain point in time.
Example: Class1 is associated with Class2
Patient takes Drug
Patient < is taken by Drug
Sample extension for Patient: Extension of an association
In the table:
Each column represents an attribute of the class. Each row is an instance of the class.
, A class can be related to itself.
Recursive association: object in class associates to another object in the same class
Example: Barack isMarriedTo Michelle (Barack and Michelle are both part of class Person)
Role names shows the role played by an object in an association.
This can be added at the respective end of an association line.
Example: Person has Person as wife
Person has Person as husband
Verbalization of models
- Important technique for explaining models and formal representations
- To validate models in the communication with customers and users
- Model fragments are expressed in some form of controlled English
- Such controlled English has a logical semantics
Integrity constraints
- Requirements on admissible states of IS
- Static rather than dynamic (state changes)
- Types of integrity constraint:
• Attribute
• Association multiplicity
• Uniqueness
• Exclusive-or
Association multiplicity constraints: define for an association how many objects of one participating
class can be associated with how many objects of the other one
• Any restriction/requirement on the number of objects of one class allowed to be linked to an
object of the other class
• Use in class diagram
• Put on association ends
• Each object of class A is linked to x..y objects of class B
Rules:
o 1 = 1..1
o Default is 0..*
• Two interpretations
o Historic: constraint ranges over current and previous
states of the UoD
➔ Used for patient regristration
Example Patient ----------- Consult
1 0..*
o Snapshot: constraint ranges over current state of UoD
➔ Used for library
Example Patient ----------- Consult
1 0..1
Multiplicity constraints can be verbalized. In their positive form, these verbalizations use the key
words each and at most one for unique links and at least one for mandatory links.
DATA MODELING
Introduction to Management Information Systems
Business objectives for Information Systems
• Operational excellence
Information Systems can improve efficiency, which means more profit.
• New products, services, and commercial business models
Commercial business model describes how a company produces, delivers, and sells its
products and services.
• Customer and supplier intimacy
• Improved decision making
• Competitive advantage
• Survival
Information Systems: set of interrelated components that manage information to support an
organization in
- decision making and control
- problem analysis and creation of new products
plus their organizational, technological, and people context.
Components are realized using Information Technology (IT), e.g. Hardware and Software.
Data: raw facts and figures without meaning of their own
It needs to be processed by IS to become information (data in meaningful, useful form).
Data -> IS -> Information
Information Systems ≠ Information Technology (IT)
Introduction to Data Modeling
Functions of Information Systems
• Represent data about entities in the problem domain
• Present and manipulate represented data
We use models to map the complex reality of a business domain and simplify it. A model only
contains those things which are considered relevant for the information system to be developed.
Two general data models:
• Model of problem domain (designed by: interview users, looking at existing data/IS)
Clarify the understanding for a domain and is input in the design and development of an IS
• Model of IS representation
Entity = real world thing about which Information System
stores information
Relation = connection between entities
Attribute = property of entity (significant piece of data
containing values that describe each instance of that class)
Different entities can share the same attributes, but with different attributes values (different states).
,Problems: an IS needs to
- distinguish different states of same entity
- distinguish different entities with same state
Solution: each entity gets identifier (attribute or collection of attributes) which is unique and remains
constant over entity life time.
Entity type = abstraction of common structure of entities
It has attributes. Instances share those attributes.
Example: Patient with attributes: patient number, name, gender, date of birth.
In UML (Unified Modeling Language):
• An entity is called an object.
Object is tangible (physical, like patients, cards) or intangible (conceptual, like diagnoses).
Existing objects from a class form its population.
• An object has attributes which have values – value of an attribute may change over time.
• Link = relationship between two or more objects (representing by a line which connects the
objects and a short description)
• An entity/object type is called an class – classifies all objects of a certain type and is visualized
as a rectangle that is labeled with the name of this class, this name has to be unique within
the diagram.
You get in trouble, if there is another patient whose name is also Stef van Bracht, because you use the
names of patients to identify the patient objects, better is a number as identifier, this is unique.
➔ Object identifiers (OID) are attributes of objects that ensure that they can be identified
among all other objects.
Association = relation between classes (link is instance of association)
Add short description by the line
Read it from left to right; exception -> when arrow pointing in other direction (inverse)
Population of an association is the set of all corresponding links that are instances of this association
at a certain point in time.
Example: Class1 is associated with Class2
Patient takes Drug
Patient < is taken by Drug
Sample extension for Patient: Extension of an association
In the table:
Each column represents an attribute of the class. Each row is an instance of the class.
, A class can be related to itself.
Recursive association: object in class associates to another object in the same class
Example: Barack isMarriedTo Michelle (Barack and Michelle are both part of class Person)
Role names shows the role played by an object in an association.
This can be added at the respective end of an association line.
Example: Person has Person as wife
Person has Person as husband
Verbalization of models
- Important technique for explaining models and formal representations
- To validate models in the communication with customers and users
- Model fragments are expressed in some form of controlled English
- Such controlled English has a logical semantics
Integrity constraints
- Requirements on admissible states of IS
- Static rather than dynamic (state changes)
- Types of integrity constraint:
• Attribute
• Association multiplicity
• Uniqueness
• Exclusive-or
Association multiplicity constraints: define for an association how many objects of one participating
class can be associated with how many objects of the other one
• Any restriction/requirement on the number of objects of one class allowed to be linked to an
object of the other class
• Use in class diagram
• Put on association ends
• Each object of class A is linked to x..y objects of class B
Rules:
o 1 = 1..1
o Default is 0..*
• Two interpretations
o Historic: constraint ranges over current and previous
states of the UoD
➔ Used for patient regristration
Example Patient ----------- Consult
1 0..*
o Snapshot: constraint ranges over current state of UoD
➔ Used for library
Example Patient ----------- Consult
1 0..1
Multiplicity constraints can be verbalized. In their positive form, these verbalizations use the key
words each and at most one for unique links and at least one for mandatory links.
