Transcript Example of DFD

Example of DFD
Vijay L. Vora
(Assist. Professor, MCA Department)
Murlidhar College,
Bhavnagar Road, Rajkot
Symbols which are use to Create DFD
Things keep in mind while creating DFD
How To create DFD
1.
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4.
Find out all possible entities.
Find out activity/process of system
Find out additional activity/process
Construct Context-Level DFD , Level-1, and Level-2 DFD
OR
Construct Context-Level, Level-0 and Level-1 DFD
OR
Construct Context-Level, Diagram 0, and Child Diagram
• Context-Level :
–Representation of Overview of Desired
system
• Level-1 :
–Representation of Main Processes of System
• Level-2 :
–Detailed Representation of Main Process
(Representation of sub-processes)
Example : 1
• The University runs various diploma, graduation and
post-graduation courses such as DE, DPharm, BE,
MBA, MCA, ME, MPharm, etc. The courses follow
semester pattern and under each course various
subjects are taught. Students seek admission to these
courses and if found eligible, the student is enrolled
for the requested course. There are several faculty
members in the University who teach the various
subjects of these courses. The subject teacher
conducts semester examinations for the concerned
subject at the end of the semester and the
students’ performance is recorded. Even if a student
is unable to pass a subject, he is promoted to the
next semester but has to reappear for that subject
examination again and clear his backlog.
Draw Context-Level, Level-1 and Level-2 DFDs
Possible Entity and Processes
• Entity
– Student
– Faculty
• Activity/Process
– Student Registration
– Examination
– Result
DFD Example :1
Context Level
Student Registration
Student
Enroll Detail
Result
DFD Example :1
Examination
Faculty
Level - 1
Registration Detail
Enrollment No.
Student
AnswringQuestions
Student
Examination
Faculty
Enroll no
Result Detail
Student
DFD Example :1
Level - 2
Process : 1
Registration Detail
Registration Data
Registration Data
Valid Student Data
Enrollment No.
DFD Example :1
(Level – 2 Continue… )
Process : 2
Exam Detail
Appeared Student
Exam Data
Student Unable to Pass.
Exam Data
Result
Answering question
Answers
Exam Data
DFD Example :1
Result
(Level – 2 Continue… )
Enrollment number
Enrollment No.
DFD Example :1
Process : 3
Result Detail
Data Available
Result
Example : 2
• ABC project co. is a firm which hires approximately 350 engineers
of different expertise. The company keep record of all employees,
their skills, project assigned and their departments. New engineers
are hired by the HR manager based on the data in the application
form and evaluations collected from other managers who
interview the job candidates. Employees may apply at any time of
the year. Engineering managers notify the HR manager when a
job opens and list the characteristics necessary for the candidate
to be eligible for the job. The HR manager compares the
qualifications of the available applicants with the qualifications
specified by the engineering managers and the schedule the
interviews between the managers and three best candidate from
the pool. After receiving evaluations of each interview from the
manager the HR manager makes the hiring decision based upon
the evaluation and application of the candidate and the
characteristic of the job and then notifies the interviewees and the
manager about the decision. Applicants with rejected application
are retained applications are retained for one year. When hired
the new employee completes a nondisclosure agreement which is
filled with other information of employee.
Draw Context-Level, Level-1 and Level-2 DFDs.