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Data Flow Diagrams Student Philosophy Club
Data Flow Diagrams
Student Philosophy Club
Business Philosophy Club• Business Philosophy Club (BPC) is a
student group at Oakland University. • The club exists to talk about the
philosophical foundations of business, listen to guest speakers and become better, more aware business people.
• The club meets regularly and issues an annual report to its advisors and sponsors, who are OU professors.
System Goals• The BPC would like to systematize their
activities.• The goals of the BPC include maintaining
membership, having good meetings, and providing advisors and sponsors with reports.
Decomposition of Goals
BPC Goals
MaintainMembership
Run GoodMeetings
Provide ValidReports
SubsubGoal 1.1
SubsubGoal1.2
SubsubGoal1.3
SubsubGoal2.1
SubsubGoal2.2
SubsubGoal2.3
SubsubGoal3.1
SubsubGoal3.2
SubsubGoal3.3
All systems, especially information systems, have goals. These goals can be “decomposed” or broken down into subgoals and the
subgoals further broken down into subsubgoals, etc.
Goals into Processes• Each goal corresponds to an information
process: Maintaining membership requires a process to
handle members and their information Having good meetings requires a process to
schedule and report on meetings Good reporting needs a process to
accumulate the information needed for the annual and ad hoc reports
Decomposition and Processes
System
Process 1:Handle
Membership
Process 2:Run GoodMeetings
Process 3:Provide Valid
Reports
Process 1.1
Process 1.2
Process 1.3
Process 2.1
Process 2.2
Process 2.3
Process 3.1
Process 3.2
Process 3.3
Goals are associated with processes. The “success” of each process means reaching the associated goal. In turn, that means
that each process’s success depends on success of subprocesses.
Data Flow Diagram: Basic Elements
Process Box
Identifier
Process Name
1.0 or 3.4.2, for example
Eg. “Register
New Member”
Data Flow
Data Store
External Actor
Iden
tifie
r
Data Store Name
Identifier
Actor Name
“Member Name” for example
Data Flow Name
“Member List” for example
“A” for example
“p” for example
“Applicant” for
example
Membership Process• Business Philosophy Club (BPC) is a student
group. It is open only to students at Oakland University in their third or fourth years who have major status in the SBA. Members pay a $10 registration fee. There are no other costs (such as annual membership). There are no other membership hurdles.
• The application process consists of two subprocesses: An initial application query to determine eligibility and a process to handle the registration payment.
Data Flow Diagram: Basic Structures
1.1
Determine Eligibility
A
Applicants
a
Appli-cant
Applicant-Info
Applicant Questions
Applicant Eligibility Process
Valid Application
Preliminary Applicant Decision
Data Flow Diagram: Basic Structures
1.2
Approve Application
A
Applicants
a
Appli-cant
Applicant-Payment
Applicant Approval Process
Application Info
Applicant Members’p Approval
Applicant Approval Data
The Improvement Goal• Some of the current processes are
inefficient.• Some may be problematic in that the
information used or generated is wrong or misleading and may lead to poor decisions.
• Some of the processes are inefficient or may be useless!
Data Flow Diagram: Basic Laws 1
Xx.yy
Process
Law of Conservation of Information
Resulting Data FlowIncoming Data Flow 1
Incoming Data Flow 2
Incoming Data Flow 3
Information cannot come from nowhere. The result of any process must be traceable to the sum of the
data flows entering the process.
BPC Meetings• Meetings are held about monthly, although
the schedule isn’t rigidly fixed because the membership is so busy.
• Members like to meet at the OC, but sometimes their favorite rooms aren’t available, nor are the members and the officers.
• In the past, rooms to large or too small or incompatible with desired use were reserved
Data Flow Diagram: Basic Laws 1 (Example)
2.1
ScheduleMeeting
Law of Conservation of Information
Scheduled Meeting Information
Attendee Information
Venue Information
Meeting properties
The next meeting depends on the availability of the attendees, the availability of the room, and the type of meeting to be scheduled such as whether this is
a philosophical debate or business meeting
Data Flow Diagram: Basic Laws 2
PP.qq
Process
Law of Utilization of Information
Resulting Data FlowIncoming Data Flow 1
Incoming Data Flow 2
Incoming Data Flow 3
Information cannot go nowhere. The result of any process must depend on ALL of the data flows
entering the process.
Meeting Minutes• To aid organizational memory, the minutes
of each meeting are written up by the BPC scribe.
• These minutes are based on notes that the scribe takes.
• Sometimes the chair of the meeting “corrects” the minutes with his or her own comments.
Data Flow Diagram: Basic Laws 2 (Example)
2.3
Create Minutes
Law of Utilization of Information
Meeting MinutesMeeting Notes
Schedule Information
Chairperson Wishes
The minutes of a meeting depend only on the notes taken at the meeting and additional information
about scheduling, NOT what the chairperson wished had happened at the meeting
Data Flow Diagram: Basic Laws 3
AA.bb
Process
Law of Logical Data Flow
Resulting Data FlowIncoming Data Flow 1
Incoming Data Flow 2
Incoming Data Flow 3
Information flows reflect logical dependency. Results of processes reflect a logical
transformation of all of the inputs.
Reporting• An annual report of the meetings and
finances is produced each year for the advisors and sponsors.
• In the past, the annual report was able to include audited financial statements, but because of various circumstances, the annual report has had to be produced early.
Data Flow Diagram: Basic Laws 3 (Example)
3.4
Create Annual Report
Law of Logical Data Flow
Annual ReportMeeting Minutes
Chairperson Wishes
Next Year’s Audited Statements
The annual report cannot include a set of financial statements not available at the time the report is
due.
Data Flow Diagram: Basic Laws 4
AA.bb
Process
Law of Data Integrity
Resulting Data FlowIncoming Data Flow 1
Access to information across the system boundary must be through a system process. Direct access
to data bases is not (generally) allowed.
A
Data Store
Ad-Hoc Reporting• Sponsors and advisors are really keen to
know about meetings and sometimes they come into the office and look at the reports before they are generated.
• This has led to misunderstanding, especially if unapproved minutes based on poorly-taken notes are read.
Data Flow Diagram: Basic Laws 4 (Example)
3.1
Inform Advisor
Law of Data Integrity
Ad Hoc ReportAd HocReport Request
Access to information across the system boundary must be through a system process. Direct access
to data bases is not (generally) allowed.
A
Data StoreAdvisor
AdvisorAdvisor
The Whole Shebang
0
Student Philosophy Club Information System
1.0
Handle Members’p
2.0
Hold Meetings
3.0
Produce Reports
Members
Appli-cants
Sponsors
A M’Ship B Meetings C Reports
Advisors
