Object Analysis and Design has emerged as the most practiced method for analysis and design of information system. An object is any thing of interest in the real world that is being modeled. For more such innovative content on management studies, join WeSchool PGDM-DLP Program: http://bit.ly/ZEcPAc

1. I.T. for Management
Section2
Chapter 10
Determining Information Need
Object analysis

2. Determining Information Need
Object analysis
Object Analysis & Design
OOAD has emerged as one of the most practiced
method for analysis & design of information
system
The OOAD helps to conceptualize a system in a
very Generic fashion and yet relate very closely to
the real world system
The OOAD offers the benefit of process, structure
and data all in one Seamless technology

3. Determining Information Need
Object analysis
What is an Object ?
An object is any thing of interest in the real world
that is being modeled
Properties of objects:
Unique Identifier
Plays role in the system
Described by attributes

4. Determining Information Need
Object analysis
Typical Objects
External entities
Things
Occurrences or events
Roles

5. Determining Information Need
Object analysis
Typical Objects
Organizational units
Places
Structures

6. Determining Information Need
Object analysis
Typical Objects (Examples)
Physical objects :
Desks ,computers ,Text books etc.
Human Object
Faculty,Student etc.
Conceptual objects:
Course,Batch,Subject
Documentation related:
Invoice ,ledger,Delivery invoice

7. Objects View of the world Vs Dataflow view
Data flow analysis believes that an information
system is a combination of flow, store and
Transformation of data,which the system
must be able to demonstrate
Object view of the information system
suggests that the system is composed of several
objects
The study of information system is really
the understanding of the desired behavior of a
system to various external and internal

8. Objects Oriented approach (OOA):
The approach to conducting an OOA is as follows
•Study the system
•Identify as many objects as possible
•Understand the object relationship
object: automobile
attributes:
make
model
body type
price
options code

9. Objects Oriented approach (OOA)
The approach to conducting an OOA is as follows
•Study the system
•Identify as many objects as possible
•Understand the object relationship
object: automobile
attributes:
make
model
body type
price
options code

10. Objects Oriented approach (OOA)
What is a Relationship
Relationship : indicates
“connectedness”
Properties:
Several instances can
exist
Objects can be related

11. Determining Information Need
Object analysis
Objects Oriented approach (OOA)
Cardinality and Modality
Cardinality: Number of occurrence
(1:1) one to one
(1:m) one to many
(m:n) many to many
Modality: Relationship is optional /
mandatory

12. Objects Oriented approach (OOA)
Thus for instance in one school teachers teaches
60 students,guides upto 10 students & mentor
for 3 student.
Each of these indicates the Cardinality of
relation. Cardinality also termed as business
rules, for instance other school numbers could
be different
As a analyst it is important to identify these
rules
The cardinality rules have a profound impact
on the Design of the business system

13. Objects Oriented approach (OOA)
Identify business events & object related events
The events related to the objects are something
that can or has happened
Events can be Singleton events where in the
objects generates its own events and then
responds.
For example Events related to Student object:
Comes late, remains absent,Attends lecture
appears exam

14. How to use Event Analysis
• System is sum of object behavior
A thorough analysis of events at the system
level as well as object level leads to a
comprehensive list of behaviors which the
system must be able to demonstrate.
• The list of events acts as a Checklist for
conducting the system analysis
The checklist helps in improving the quality
of the analysis
• Thus the list of behaviors also helps in
working out the scope and size of the
programs to be developed

15. How to use Event Analysis
• Associated programs with objects
Usually the object which seems to have a
Control over the behavior is the place where the
method needs to be assigned to.
• Data base design
OOA naturally leads to database design
Each object becomes table in a database for ex
student,faculty
Each relationship becomes table in a database
for ex. Teacher mentor examiner

16. How to use Event Analysis
Keys & Attribute
What are keys:
Keys are essentially identifiers used to identify an
object in a table
Primary keys Apart from storage the ids make it
easy to uniquely identify an object in a table.Such
ids/keys are known as primary key
Combined key
In a table such as mentor Mr. Mehta is mentor for
several students hence his id will appear several
times in a table.
Thus it is not a unique key.Thus every row in the
mentor table is unique but it requires a combined

17. How to use Event Analysis
Keys & Attribute
Secondary keys
Non unique keys are also known as secondary keys
Secondary keys are quite often used for answering
certain queries
Foreign Keys
Keys in a database, which help to identify objects
stored in another table, are known as Foreign Keys
.For example student id key used in any other table
like attendance table helps us to trace name stored
in the student master table. Foreign Keys are
useful to connect data across different tables in a
database

18. Determining Information Need
Object analysis Section2
End of Chapter 10