1. Project 1 Guide System Analysis & Design
Seminar Second Semester
1437/1438 – 2016/2017
Presented by:
Ms. Hend Al-Bassam
Ms. Abeer Al-Drees
11/16/2018

2. Plan Introduction System Analysis & Design Object Oriented analysis
Structured Analysis
Database
11/16/2018

3. Introduction After Literature Review and Background phases
System analysis & design phase
User & System requirements
Structured Approach
Object Oriented Approach
Design approach
11/16/2018

4. System analysis & Design
User Requirements and System Specifications
Analysis
Design
Conclusion
11/16/2018

5. System analysis & Design
User Requirements Definition:
The UR stage is considered as the ‘concept' or ‘problem definition‘ stage;
UR frequently derive directly from a spontaneous idea or thought
UR should be gathered based on the user needs;
UR should be clarified through criticism and experience of existing software and prototypes;
UR should be approved through interviews and surveys;
UR should be realistic (clear, verifiable, complete, accurate, feasible).
11/16/2018

6. System analysis & Design
System Requirement Specification
A detailed statement of the results that a system is requested to reach. A good specification gives a complete statement of what the system is to do,
A system requirements specification is normally produced in response to a user requirements.
11/16/2018

7. System analysis & Design
Object Oriented Analysis (still growing):
Population of interacting objects of a system
Structured Analysis (still in use today):
The traditional data or functional views
11/16/2018

8. System analysis & Design
Structured Approach
1- Use Case diagram
2- Context level DFD
3- Level-0 DFD
4- Subsequent levels DFDs (max 3 levels)
5- ER Diagram (if needed)
6- DB Shema & Dictionary (Data Design) if needed
7- Architectural Design
8- Structured English/ Decsion Tables/ Decision trees/ Flowcharts (for major processes only) – (Component Design)
9- Interface design
Object Oriented Approach
1- Use Case diagram
2- Use Cases Descriptions
3- Conceptual Diagram
4- Sequence Diagram
5- Class Diagram
6- ER Diagram (if needed) -
7- DB Shema & Dictionary (Data Design) if needed
7- Architectural Design
8- Pseudo code/ Algorithms/ Flowcharts (component Design)
9- Interface design
11/16/2018

9. Object Oriented Analysis
11/16/2018

10. Use Case Diagram
It describes the main system functions from the standpoint of an external observer.
Used during requirements elicitation to represent external behavior.
It emphasize on what the system does rather than how it.
It is created during the early stages of a project – during the analysis phase rather than during the design phase.
It provides a high-level view of what the system does and who uses it.
It provides the basis for determining the user interfaces (UIs) to the system
11/16/2018

11. Example Use cases diagram
11/16/2018

12. Example
11/16/2018

13. Example
11/16/2018

14. Conceptual (Domain) Model
A domain model illustrates meaningful concepts in a problem domain.
It’s a representation of real-world things, not software components.
It’s a set of static structure diagrams; no operations are defined.
It may show:
Concepts
Attributes of concepts.
Associations between concepts
11/16/2018

15. Domain Model
11/16/2018

16. Sequence diagrams: An Interaction Model
Sequence diagrams are part of the UML and are used to model the interactions between the actors and the objects within a system.
The objects and actors involved are listed along the top of the diagram, with a dotted line drawn vertically from these.
Interactions between objects are indicated by annotated arrows.
Detail how operations are carried out
Dynamic Diagrams
Organized according to time
The time progresses as you go down the page
The objects involved in the operation are listed from left to right according to when they take part in the message sequence.
Create a sequence diagram for each scenario
11/16/2018

17. Sequence Diagrams :Register :ProductCatalogue Sale :ProductSpec
addLineItem(itemID, quantity)
1. Spec=getSpecification(itemID)
1.1 Spec=Find(itemID)
2. makeLineItem(spec,quantity)
2.1 sli= Create(spec,quantity)
:SalesLineItem
2.2 Add(sli)
11/16/2018

18. Class Diagram
A class diagram shows the existence of classes and their relationships in the logical view of a system.
UML modeling elements in class diagrams:
Classes and their structure and behavior.
Association, aggregation, dependency, and inheritance relationships.
Multiplicity and navigation indicators.
Role names.
11/16/2018

19. Class Diagram
11/16/2018

20. Structured Analysis
11/16/2018

21. System Analysis Basic principle: problem partition
Partition with regard to what
Object Object Oriented analysis
Function - Structural analysis
Data Flow Modeling (DFD)
11/16/2018

22. Data Flow Modeling
Widely used; focuses on functions performed in the system
Uses data flow diagrams (DFDs) and functional decomposition in modeling
11/16/2018

23. Steps in Building DFDs Build the context diagram
Create DFD fragments for each scenario
Organize DFD fragments into level 0
Decompose level 0 DFDs as needed
Validate DFDs with user
11/16/2018

24. Subsequent DFD levels
11/16/2018

25. Context Diagram Shows the overall business process as just one process
Shows all the outside entities that receive information from or contribute information to the system
11/16/2018

26. Level 0 Diagram
Shows all the processes that comprise the overall system
Shows how information moves from and to each process
Adds data stores
11/16/2018

27. Level 0 Diagram
11/16/2018

28. Level 1 Diagrams
Shows all the processes that comprise a single process on the level 0 diagram
Shows how information moves from and to each of these processes
Level 1 diagrams may not be needed for all level 0 processes
11/16/2018

29. Level 2 Diagrams
Shows all processes that comprise a single process on the level 1 diagram
Level 2 diagrams may not be needed for all level 1 processes
Correctly numbering each process helps the user understand where the process fits into the overall system
11/16/2018

30. Composite & Elementary Flows
11/16/2018

31. DFD – Common Errors
Black Hole
Gray Hole
Miracle
11/16/2018

32. Illegal Data Flows
11/16/2018

33. DFD drawing – common errors
Unlabeled data flows
Missing data flows
Extraneous data flows
Consistency not maintained during refinement
Missing processes
Too detailed or too abstract
11/16/2018

34. Logic Modeling
Data flow diagrams do not show the logic inside the processes.
Logic modeling involves representing internal structure and functionality of processes:
Structured English
Decision Tables
Decision Trees
11/16/2018

35. Logic Modeling
11/16/2018

36. Logic Modeling
11/16/2018

37. Logic Modeling
11/16/2018

38. Database
11/16/2018

39. 11/16/2018

40. Weak Entity
11/16/2018

41. DB Schema
How to derive a set of relations from a conceptual data model.
11/16/2018

42. Student (Student_ID, Name, DOB) Student_Phone ( Student_ID, Phone)
Enroll (Student_ID, Code, Grade)
Course (Code, Name, Instructor_ID)
Instructor (Instructor_ID, Name, city, street)
11/16/2018

43. Section (Section#, Code, Enrollment_limit)
Course (Code, Name)
11/16/2018

44. DB Dictionary
Entity dictionary
11/16/2018

45. General term describing all enrolled students.
Entity Name
Description
Aliases
Occurrence
Student
General term describing all enrolled students.
Students can enroll in several courses.
Course
A general term describing all courses offered by the university.
Each course is taught by one teacher.
Instructor
The person who teaches courses at the university.
Teacher
The instructor can teach many courses.
11/16/2018

46. DB Dictionary
Relationships dictionary
11/16/2018

47. Entity Name Multiplicity Relationship Student 0..* Enroll Course
Teaches
Instructor
1..1
11/16/2018

48. DB Dictionary
Attributes dictionary
11/16/2018

49. Uniquely identifies instructor. varchar 5 no Y
Entity name
Attribute
Description
Data Type
Length
Nulls
Multi-valued
Default Value
Range PK CK
Instructor
Instructor_ID
Uniquely identifies instructor.
varchar 5 no Y
Name
Name of instructor 30
Address
City
The city where the instructor lives. 10
Street
The street where the instructor lives. 20
11/16/2018

50. Thank you
11/16/2018

51. References
Guide to the User Requirements Definition phase, ESA PSS Issue 1 Revision 1 March 1995
Modern Systems Analysis and Design by Jeffrey A. Hoffer, Joey George, Joe A. Valacich
11/16/2018