Suche senden
Hochladen
S3 dfd1 context diagram pdf
•
1 gefällt mir
•
2,690 views
aviy1966
Folgen
Technologie
Business
Melden
Teilen
Melden
Teilen
1 von 11
Jetzt herunterladen
Downloaden Sie, um offline zu lesen
Empfohlen
Class 10 Unit - 6 Digital Documentation.pptx
Class 10 Unit - 6 Digital Documentation.pptx
Gargee19
Excel Exercise
Excel Exercise
Kereen Tatham
Word practical questions for exercises
Word practical questions for exercises
Hari993901
Macros in ms word
Macros in ms word
ahmreenmalik
Full Presentation on Notepad
Full Presentation on Notepad
manish chaturvedi
Notepad ++
Notepad ++
Dileep Choudhary
Introduction to computers by abdul rahaman
Introduction to computers by abdul rahaman
Abdul-rahaman Bin Abubakar Suleman
How to make a result sheet of students using MS EXCEL
How to make a result sheet of students using MS EXCEL
Anu Radha
Empfohlen
Class 10 Unit - 6 Digital Documentation.pptx
Class 10 Unit - 6 Digital Documentation.pptx
Gargee19
Excel Exercise
Excel Exercise
Kereen Tatham
Word practical questions for exercises
Word practical questions for exercises
Hari993901
Macros in ms word
Macros in ms word
ahmreenmalik
Full Presentation on Notepad
Full Presentation on Notepad
manish chaturvedi
Notepad ++
Notepad ++
Dileep Choudhary
Introduction to computers by abdul rahaman
Introduction to computers by abdul rahaman
Abdul-rahaman Bin Abubakar Suleman
How to make a result sheet of students using MS EXCEL
How to make a result sheet of students using MS EXCEL
Anu Radha
Queries
Queries
lindy23
Revision Notes IT CODE 402 Class 10.pdf
Revision Notes IT CODE 402 Class 10.pdf
ManasGupta211804
Microsoft access
Microsoft access
ReshmiSV
basic shortcut keys in computer
basic shortcut keys in computer
Hirfan Ullah
Ms excel excersices
Ms excel excersices
HEENA PRUTHI
Microsoft office course outline
Microsoft office course outline
firstlogichelpdesk
Word 2007-Header And Footer Basics
Word 2007-Header And Footer Basics
Oklahoma Dept. Mental Health
Ms word Presentation
Ms word Presentation
Madhab Behera
Ms word, access, powerpoint and internet
Ms word, access, powerpoint and internet
RajaKrishnan M
Basic Computer Skills Seminar
Basic Computer Skills Seminar
Meridian Career Institute
84 identify group keys on the keyboard and their functions
84 identify group keys on the keyboard and their functions
Paul Gonzales
Shortcut keys of windows operating system and windows
Shortcut keys of windows operating system and windows
DEV YADAV
The Five Generations of Computers
The Five Generations of Computers
imtiazalijoono
Word Lecture 1
Word Lecture 1
Christinliao
Introduction to keyboard
Introduction to keyboard
SanjuktaSahoo5
Excel for beginners class 1
Excel for beginners class 1
Carlstadt Public Library
Evolution of Computer
Evolution of Computer
Ohi Alam
Introduction to Google Forms
Introduction to Google Forms
Claire Amos
ICT - Lecture Notes 2.pdf
ICT - Lecture Notes 2.pdf
HonKencyTress
Word exercises (1)
Word exercises (1)
ruelcdogma
Entity-relation-diagram
Entity-relation-diagram
zenek1234
S6 advanced issues in erd pdf
S6 advanced issues in erd pdf
aviy1966
Weitere ähnliche Inhalte
Was ist angesagt?
Queries
Queries
lindy23
Revision Notes IT CODE 402 Class 10.pdf
Revision Notes IT CODE 402 Class 10.pdf
ManasGupta211804
Microsoft access
Microsoft access
ReshmiSV
basic shortcut keys in computer
basic shortcut keys in computer
Hirfan Ullah
Ms excel excersices
Ms excel excersices
HEENA PRUTHI
Microsoft office course outline
Microsoft office course outline
firstlogichelpdesk
Word 2007-Header And Footer Basics
Word 2007-Header And Footer Basics
Oklahoma Dept. Mental Health
Ms word Presentation
Ms word Presentation
Madhab Behera
Ms word, access, powerpoint and internet
Ms word, access, powerpoint and internet
RajaKrishnan M
Basic Computer Skills Seminar
Basic Computer Skills Seminar
Meridian Career Institute
84 identify group keys on the keyboard and their functions
84 identify group keys on the keyboard and their functions
Paul Gonzales
Shortcut keys of windows operating system and windows
Shortcut keys of windows operating system and windows
DEV YADAV
The Five Generations of Computers
The Five Generations of Computers
imtiazalijoono
Word Lecture 1
Word Lecture 1
Christinliao
Introduction to keyboard
Introduction to keyboard
SanjuktaSahoo5
Excel for beginners class 1
Excel for beginners class 1
Carlstadt Public Library
Evolution of Computer
Evolution of Computer
Ohi Alam
Introduction to Google Forms
Introduction to Google Forms
Claire Amos
ICT - Lecture Notes 2.pdf
ICT - Lecture Notes 2.pdf
HonKencyTress
Word exercises (1)
Word exercises (1)
ruelcdogma
Was ist angesagt?
(20)
Queries
Queries
Revision Notes IT CODE 402 Class 10.pdf
Revision Notes IT CODE 402 Class 10.pdf
Microsoft access
Microsoft access
basic shortcut keys in computer
basic shortcut keys in computer
Ms excel excersices
Ms excel excersices
Microsoft office course outline
Microsoft office course outline
Word 2007-Header And Footer Basics
Word 2007-Header And Footer Basics
Ms word Presentation
Ms word Presentation
Ms word, access, powerpoint and internet
Ms word, access, powerpoint and internet
Basic Computer Skills Seminar
Basic Computer Skills Seminar
84 identify group keys on the keyboard and their functions
84 identify group keys on the keyboard and their functions
Shortcut keys of windows operating system and windows
Shortcut keys of windows operating system and windows
The Five Generations of Computers
The Five Generations of Computers
Word Lecture 1
Word Lecture 1
Introduction to keyboard
Introduction to keyboard
Excel for beginners class 1
Excel for beginners class 1
Evolution of Computer
Evolution of Computer
Introduction to Google Forms
Introduction to Google Forms
ICT - Lecture Notes 2.pdf
ICT - Lecture Notes 2.pdf
Word exercises (1)
Word exercises (1)
Andere mochten auch
Entity-relation-diagram
Entity-relation-diagram
zenek1234
S6 advanced issues in erd pdf
S6 advanced issues in erd pdf
aviy1966
Apresentação sobre ipv6
Apresentação sobre ipv6
Leandro Rodrigues
Lecture 10 documentation techniques -transaction processing- james a. hall b...
Lecture 10 documentation techniques -transaction processing- james a. hall b...
Habib Ullah Qamar
Context Diagram
Context Diagram
Deal Up
Sub Netting
Sub Netting
Lilesh Pathe
IP Address
IP Address
Rahul P
IP Address
IP Address
Sameer Alam
CCNA Exploration 2 - Chapter 6
CCNA Exploration 2 - Chapter 6
Irsandi Hasan
Easy IP Addressing and Subnetting Manual for Starters
Easy IP Addressing and Subnetting Manual for Starters
S Khawaja
HSC Context and data flow diagrams ( DFD )
HSC Context and data flow diagrams ( DFD )
greg robertson
Ip address
Ip address
Amandeep Kaur
Data Flow Diagram
Data Flow Diagram
Puneet Arora
Ip address and subnetting
Ip address and subnetting
IGZ Software house
Dfd examples
Dfd examples
Mohit
Data Flow Diagram Example
Data Flow Diagram Example
Kaviarasu D
Hype vs. Reality: The AI Explainer
Hype vs. Reality: The AI Explainer
Luminary Labs
Andere mochten auch
(17)
Entity-relation-diagram
Entity-relation-diagram
S6 advanced issues in erd pdf
S6 advanced issues in erd pdf
Apresentação sobre ipv6
Apresentação sobre ipv6
Lecture 10 documentation techniques -transaction processing- james a. hall b...
Lecture 10 documentation techniques -transaction processing- james a. hall b...
Context Diagram
Context Diagram
Sub Netting
Sub Netting
IP Address
IP Address
IP Address
IP Address
CCNA Exploration 2 - Chapter 6
CCNA Exploration 2 - Chapter 6
Easy IP Addressing and Subnetting Manual for Starters
Easy IP Addressing and Subnetting Manual for Starters
HSC Context and data flow diagrams ( DFD )
HSC Context and data flow diagrams ( DFD )
Ip address
Ip address
Data Flow Diagram
Data Flow Diagram
Ip address and subnetting
Ip address and subnetting
Dfd examples
Dfd examples
Data Flow Diagram Example
Data Flow Diagram Example
Hype vs. Reality: The AI Explainer
Hype vs. Reality: The AI Explainer
Ähnlich wie S3 dfd1 context diagram pdf
S4 dfd2 detail level diagram pdf
S4 dfd2 detail level diagram pdf
aviy1966
Data flow diagram
Data flow diagram
Nidhi Sharma
Building a data warehouse
Building a data warehouse
Ester Daci
Artificially Intelligent Investment Risk Calculation system based on Distribu...
Artificially Intelligent Investment Risk Calculation system based on Distribu...
iosrjce
D017612529
D017612529
IOSR Journals
Understanding IDP: Data Validation and Feedback Loop
Understanding IDP: Data Validation and Feedback Loop
Infrrd
Recording Transaction
Recording Transaction
Patricia Viljoen
Running Head PROJECT DELIVERABLE 31PROJECT DELIVERABLE 310.docx
Running Head PROJECT DELIVERABLE 31PROJECT DELIVERABLE 310.docx
todd581
Data flow diagrams dfd
Data flow diagrams dfd
Alam Fareed
Course Outline Ch 2
Course Outline Ch 2
Megan Espinoza
Survey on An effective database tampering system with veriable computation a...
Survey on An effective database tampering system with veriable computation a...
IRJET Journal
1. What are the business costs or risks of poor data quality Sup.docx
1. What are the business costs or risks of poor data quality Sup.docx
SONU61709
Week10 Analysing Client Requirements
Week10 Analysing Client Requirements
hapy
A Holistic Approach to Property Valuations
A Holistic Approach to Property Valuations
Cognizant
Smarter Document Capture
Smarter Document Capture
Desktop Imaging
System flow charts @ doms
System flow charts @ doms
Babasab Patil
The Road to Open Data Enlightenment Is Paved With Nice Excuses
The Road to Open Data Enlightenment Is Paved With Nice Excuses
Toon Vanagt
Workshop on requirements and modeling at HAE 2015
Workshop on requirements and modeling at HAE 2015
Olivier Béghain
BigDataCloud Sept 8 2011 Meetup - Big Data Analytics for DoddFrank Regulation...
BigDataCloud Sept 8 2011 Meetup - Big Data Analytics for DoddFrank Regulation...
BigDataCloud
The road to open data enlightenment is paved with nice excuses by Toon Vanagt
The road to open data enlightenment is paved with nice excuses by Toon Vanagt
Opening-up.eu
Ähnlich wie S3 dfd1 context diagram pdf
(20)
S4 dfd2 detail level diagram pdf
S4 dfd2 detail level diagram pdf
Data flow diagram
Data flow diagram
Building a data warehouse
Building a data warehouse
Artificially Intelligent Investment Risk Calculation system based on Distribu...
Artificially Intelligent Investment Risk Calculation system based on Distribu...
D017612529
D017612529
Understanding IDP: Data Validation and Feedback Loop
Understanding IDP: Data Validation and Feedback Loop
Recording Transaction
Recording Transaction
Running Head PROJECT DELIVERABLE 31PROJECT DELIVERABLE 310.docx
Running Head PROJECT DELIVERABLE 31PROJECT DELIVERABLE 310.docx
Data flow diagrams dfd
Data flow diagrams dfd
Course Outline Ch 2
Course Outline Ch 2
Survey on An effective database tampering system with veriable computation a...
Survey on An effective database tampering system with veriable computation a...
1. What are the business costs or risks of poor data quality Sup.docx
1. What are the business costs or risks of poor data quality Sup.docx
Week10 Analysing Client Requirements
Week10 Analysing Client Requirements
A Holistic Approach to Property Valuations
A Holistic Approach to Property Valuations
Smarter Document Capture
Smarter Document Capture
System flow charts @ doms
System flow charts @ doms
The Road to Open Data Enlightenment Is Paved With Nice Excuses
The Road to Open Data Enlightenment Is Paved With Nice Excuses
Workshop on requirements and modeling at HAE 2015
Workshop on requirements and modeling at HAE 2015
BigDataCloud Sept 8 2011 Meetup - Big Data Analytics for DoddFrank Regulation...
BigDataCloud Sept 8 2011 Meetup - Big Data Analytics for DoddFrank Regulation...
The road to open data enlightenment is paved with nice excuses by Toon Vanagt
The road to open data enlightenment is paved with nice excuses by Toon Vanagt
Kürzlich hochgeladen
2024: Domino Containers - The Next Step. News from the Domino Container commu...
2024: Domino Containers - The Next Step. News from the Domino Container commu...
Martijn de Jong
A Year of the Servo Reboot: Where Are We Now?
A Year of the Servo Reboot: Where Are We Now?
Igalia
08448380779 Call Girls In Diplomatic Enclave Women Seeking Men
08448380779 Call Girls In Diplomatic Enclave Women Seeking Men
Delhi Call girls
CNv6 Instructor Chapter 6 Quality of Service
CNv6 Instructor Chapter 6 Quality of Service
giselly40
The 7 Things I Know About Cyber Security After 25 Years | April 2024
The 7 Things I Know About Cyber Security After 25 Years | April 2024
Rafal Los
From Event to Action: Accelerate Your Decision Making with Real-Time Automation
From Event to Action: Accelerate Your Decision Making with Real-Time Automation
Safe Software
🐬 The future of MySQL is Postgres 🐘
🐬 The future of MySQL is Postgres 🐘
RTylerCroy
IAC 2024 - IA Fast Track to Search Focused AI Solutions
IAC 2024 - IA Fast Track to Search Focused AI Solutions
Enterprise Knowledge
Factors to Consider When Choosing Accounts Payable Services Providers.pptx
Factors to Consider When Choosing Accounts Payable Services Providers.pptx
Katpro Technologies
Scaling API-first – The story of a global engineering organization
Scaling API-first – The story of a global engineering organization
Radu Cotescu
Artificial Intelligence: Facts and Myths
Artificial Intelligence: Facts and Myths
Joaquim Jorge
Advantages of Hiring UIUX Design Service Providers for Your Business
Advantages of Hiring UIUX Design Service Providers for Your Business
Pixlogix Infotech
The Codex of Business Writing Software for Real-World Solutions 2.pptx
The Codex of Business Writing Software for Real-World Solutions 2.pptx
Malak Abu Hammad
Finology Group – Insurtech Innovation Award 2024
Finology Group – Insurtech Innovation Award 2024
The Digital Insurer
Understanding Discord NSFW Servers A Guide for Responsible Users.pdf
Understanding Discord NSFW Servers A Guide for Responsible Users.pdf
UK Journal
Handwritten Text Recognition for manuscripts and early printed texts
Handwritten Text Recognition for manuscripts and early printed texts
Maria Levchenko
Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...
Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...
Neo4j
08448380779 Call Girls In Friends Colony Women Seeking Men
08448380779 Call Girls In Friends Colony Women Seeking Men
Delhi Call girls
Breaking the Kubernetes Kill Chain: Host Path Mount
Breaking the Kubernetes Kill Chain: Host Path Mount
Puma Security, LLC
Tata AIG General Insurance Company - Insurer Innovation Award 2024
Tata AIG General Insurance Company - Insurer Innovation Award 2024
The Digital Insurer
Kürzlich hochgeladen
(20)
2024: Domino Containers - The Next Step. News from the Domino Container commu...
2024: Domino Containers - The Next Step. News from the Domino Container commu...
A Year of the Servo Reboot: Where Are We Now?
A Year of the Servo Reboot: Where Are We Now?
08448380779 Call Girls In Diplomatic Enclave Women Seeking Men
08448380779 Call Girls In Diplomatic Enclave Women Seeking Men
CNv6 Instructor Chapter 6 Quality of Service
CNv6 Instructor Chapter 6 Quality of Service
The 7 Things I Know About Cyber Security After 25 Years | April 2024
The 7 Things I Know About Cyber Security After 25 Years | April 2024
From Event to Action: Accelerate Your Decision Making with Real-Time Automation
From Event to Action: Accelerate Your Decision Making with Real-Time Automation
🐬 The future of MySQL is Postgres 🐘
🐬 The future of MySQL is Postgres 🐘
IAC 2024 - IA Fast Track to Search Focused AI Solutions
IAC 2024 - IA Fast Track to Search Focused AI Solutions
Factors to Consider When Choosing Accounts Payable Services Providers.pptx
Factors to Consider When Choosing Accounts Payable Services Providers.pptx
Scaling API-first – The story of a global engineering organization
Scaling API-first – The story of a global engineering organization
Artificial Intelligence: Facts and Myths
Artificial Intelligence: Facts and Myths
Advantages of Hiring UIUX Design Service Providers for Your Business
Advantages of Hiring UIUX Design Service Providers for Your Business
The Codex of Business Writing Software for Real-World Solutions 2.pptx
The Codex of Business Writing Software for Real-World Solutions 2.pptx
Finology Group – Insurtech Innovation Award 2024
Finology Group – Insurtech Innovation Award 2024
Understanding Discord NSFW Servers A Guide for Responsible Users.pdf
Understanding Discord NSFW Servers A Guide for Responsible Users.pdf
Handwritten Text Recognition for manuscripts and early printed texts
Handwritten Text Recognition for manuscripts and early printed texts
Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...
Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...
08448380779 Call Girls In Friends Colony Women Seeking Men
08448380779 Call Girls In Friends Colony Women Seeking Men
Breaking the Kubernetes Kill Chain: Host Path Mount
Breaking the Kubernetes Kill Chain: Host Path Mount
Tata AIG General Insurance Company - Insurer Innovation Award 2024
Tata AIG General Insurance Company - Insurer Innovation Award 2024
S3 dfd1 context diagram pdf
1.
Copyright © 2009
Bahn, D., Tang, H. & Yardley, A. All Rights Reserved. ISBN: 978-1-936203-05-5 Systems Analysis and Design Learning Module Series #3 Document version Data Flow Diagrams Part 1 Creating an Intersection Table in a Relational Database Overview In this tutorial we will explain the basic symbols used in a data flow diagram, initialize a new diagram and create a context diagram depicting a Reservation System. What is a Data Flow Diagram (DFD)? A data flow diagram is a graphical process model that shows all the main requirements an information system in on diagram. It depicts Inputs Outputs Processes, and Data Storage entities. A key advantage of a DFD is that it easy to read and understand with minimal training or technical background. The symbols used in a DFD are as follows: 1
2.
Copyright © 2009
Bahn, D., Tang, H. & Yardley, A. All Rights Reserved. ISBN: 978-1-936203-05-5 City Lights Bed and Breakfast – Case Study Potential visitors to the Twin Cities call up City Lights Bed and Breakfast to inquire as to available locations to stay in over their visit to Minneapolis/St. Paul, MN. Each caller is interviewed over the phone by a bookings clerk. If the caller is interested in using the reservation service, the bookings clerk records the inquiry (the desired dates of arrival and departure, location and accommodation preferences) as a reservation request for the potential guest. The bookings clerk then identifies host accommodations that may be suitable to fulfill the reservation request. Accommodations are referenced against the current host location bookings schedule to determine if they are available during the time period that the potential guests intend to stay in the Twin Cities. After finding suitable host accommodations that appear to be available at the requested time period, the bookings clerk contacts the host to verify if the desired accommodations are available and confirm that guest demographics (as described during the initial intake survey) contain no disqualifying criteria and meet with the hosts approval. If all conditions are satisfactory, i.e. the dates are available and the host is willing to approve their stay, the bookings clerk now contacts the potential guests to confirm that the location is suitable and the guest wishes to authorize completion of the reservation transaction. With the guest’s approval, the clerk submits the guest’s credit card information to initialize a reservation transaction. After confirming the credit card information electronically (via the Credit Card Bureau) and recording the reservation, the bookings schedule is updated and notification is sent to the host confirming the booking, along with the details of the stay. Concurrently, a final reservation confirmation (letter or fax) is dispatched the guest. Creating a Context Diagram Five steps are involved: 1. Identify one process that will be placed in the middle of the diagram to represent the total information processing system. This central information process, contained within an automation boundary, will be called the System Process. 2. Identify all potential actors from the case study narrative that produce or consume data from the system. These actors are called External Entities. 3. Identify primary potential stores of data used by the system its transactions. These are called Data Stores. 4. Brainstorm and elaborate all potential streams of data that flow to and from the System Process, i.e. to or from the External Entities and Data Stores). These are called Data Flows and must always flow into or out of a process. 5. Eliminate those external entities which do not have any Data Flows connecting them to the System Process. 2
3.
Copyright © 2009
Bahn, D., Tang, H. & Yardley, A. All Rights Reserved. ISBN: 978-1-936203-05-5 Bird’s eye view of completed model How to Create our DFD in MS Visio 1. Open MS Visio. From the Menu bar, click File and select: New… Flowchart… Data Flow Diagram (US units). 3
4.
Copyright © 2009
Bahn, D., Tang, H. & Yardley, A. All Rights Reserved. ISBN: 978-1-936203-05-5 The System Process Since this is a context diagram, our first step is to insert a single System Process in the center of our diagram. This automation boundary will represent the total reservation system of City Lights B&B. 2. From the Shapes Window Pane, drag the Data Process item to the center of the workspace grid. Double-click on the shape to name it City Lights B&B Reservation System. 4
5.
Copyright © 2009
Bahn, D., Tang, H. & Yardley, A. All Rights Reserved. ISBN: 978-1-936203-05-5 The External Entities DFD also contains “External Entities” that are producers and consumers of data transformed by processes. A context DFD depicts all the significant External Entities that either input Data Flows for the system to process, or consume Data Flows that are output from the system. In our Case Study narrative, there are three such actors or External Entities: The (potential) Guest, the Host, and the Bookings Clerk (who mediates and facilitates between the other two). 3. Drag three External Entity items from the Shapes Window Pane to the workspace grid. Double-click on the shapes, one at a time, labeling them Guest, Clerk and Host respectively. . The Data Stores DFD’s also contain “Data Stores” that represent flows of data that have been stored for a while prior to being used again, or more simply data flows in storage. (Think of them like a database or file cabinet). If we identify the Data Stores in our case study, we find that we there are two: The Host Location Booking Schedule (mentioned explicitly), and the Credit Card Bureau (implied in the process of payment confirmation from an external source). 4. Drag two Data Store items from the Shapes Window Pane to the workspace grid. To add text, click Insert on the Menu bar and select Text Box. 5
6.
Copyright © 2009
Bahn, D., Tang, H. & Yardley, A. All Rights Reserved. ISBN: 978-1-936203-05-5 Data Store The Data Flows Data Flows operate in one of two directions, and can be considered from different perspectives. The Visitors perspective includes “Producing” data flows, such as: Reservation Request and Payment Information; as well as “Receiving” data flows, such as: Potential Booking Options and Confirmation of a Completed Booking. The Host’s perspective includes “Producing” data flows, such as: Confirmation of host location availability and Confirmation of Reservation Suitability; as well as “Receiving” data flows, such as: Reservation Request and Request for Suitability/Availability approval. “Other” data flows include: Confirmation of Credit Card information, Potential availability of Host Location, and Completed Reservation. ______ Note: In Visio, data flows can be represented by a curved connector or a straight-lined/angular connector. In this tutorial, we will be using the straight-lined/angular which is the default connector that the connector tool supplies: To use the connector tool, first, click the button on the toolbar; second, use the mouse to draw the connection, in the appropriate direction, on Visio work space grid. 6
7.
Copyright © 2009
Bahn, D., Tang, H. & Yardley, A. All Rights Reserved. ISBN: 978-1-936203-05-5 In the next set of steps, we will place data flows onto the diagram, identifying those flows from the perspectives of each external entity, according to the case narrative: 5. Draw the following data flows from the Guest’s Perspective: Reservation Request (guest, producing) Payment Information (guest, producing) Potential Booking (guest, receiving) Confirmation of Completed Booking (guest, receiving) 6. Draw the following data flows from the Host’s Perspective: Reservation request Availability Confirmation (host, producing) Reservation (location/dates etc.) Suitability Confirmation (host, producing) Request for Availability/Suitability confirmation (host, receiving) Request for Booking Confirmation (host, receiving) 7
8.
Copyright © 2009
Bahn, D., Tang, H. & Yardley, A. All Rights Reserved. ISBN: 978-1-936203-05-5 Based on our narrative … the potential availability of a Host location is looked up by the Bookings Clerk in the Host Locations Booking Schedule data store. Similarly, the completed reservation is posted back to the Schedule by the Clerk. 7. Draw the following Other data flows: Reservation request Availability Confirmation (host, producing) Reservation (location/dates etc.) Suitability Confirmation (host, producing) Request for Availability/Suitability confirmation (host, receiving) Request for Booking Confirmation (host, receiving) However, a closer look at the above diagram reveals that it is in violation of our key rule: All data must flow to, or from, a process! Stated differently, the DFD only shows data that undergoes transformation. Both of these data flows are in violation of this rule, since the Clerk does not represent a process, nor does any data get transformed through him/her. Therefore, the next step is to Delete the Clerk , and present the data flow, rather as in : 8
9.
Copyright © 2009
Bahn, D., Tang, H. & Yardley, A. All Rights Reserved. ISBN: 978-1-936203-05-5 8. Similarly, draw the following Other data flows: Confirmation of Credit Card Information (system receiving from external data store) 9
10.
Copyright © 2009
Bahn, D., Tang, H. & Yardley, A. All Rights Reserved. ISBN: 978-1-936203-05-5 The Final Product In this tutorial then, we learned how to construct a context data flow diagram. In Part II - the next tutorial, we will learn how to construct a Level 0 DFD which depicts the processes and data flows at the next granular level of detail; and further refine our context diagram using some advanced rules of DFD presentation. 10
11.
Copyright © 2009
Bahn, D., Tang, H. & Yardley, A. All Rights Reserved. ISBN: 978-1-936203-05-5 Systems Analysis and Design Learning Module Series #3 Document version Data Flow Diagrams Part 1 Creating an Intersection Table in a Relational Database 11
Jetzt herunterladen