CSC-331 Chapter 5

Data flow diagramming is:

Focused on the processes or activities that are performed

Decomposing a DFD means:

Breaking complex processes into a structured set of detailed diagrams

Which Data Flow Diagram shows the entire system with its environment with only one process?

Context Diagram

A data flow is:

A single piece of data

Which Data Flow Diagram does not have data stores?

context diagram

Which of the following is NOT true? a) Every process has at least one input data flow b) Every data flow connects to at least one process c) Every external entity has at least one input or one output data flow d) Every data flow has a unique name that is a verb phrase e) Every process has at least one output data flow

d) Every data flow has a unique name that is a verb phrase

A data store is:

A collection of data

A data store is:

A collection of data within a system

On a data flow diagram, there is an arrow called 'student record details'. This would be:

A data flow

A process model is:

A formal way of representing how a business system operates

The relation between use cases and data flow diagrams is generally:

Use cases are developed first and then data flow diagrams ensue

Data flows in data flow diagramming are represented by:

Arrows

On your level 0 diagram you have a process #2 and when you create a level 1 diagram for process #2, you might have processes like:

2.1, 2.2, 2.3

A payroll data flow diagram has a data-store called Accumulated Salary Data. At one stage in the DFD, a process "Calculate YTD-Taxes" gets data from that data store, updates it in the process, and writes it back out. The diagram should show:

A line out of the data store labeled: Current YTD Payroll Details; and a line into the data store labeled: Updated YTD Payroll Details

Andrea is creating a diagram model for processes (without regard to whether it is computerized or a manual process). She is probably creating

A logical process model

An external entity is:

A person, organization or system outside of the system

An external entity is:

A person, organization or system that is external to the system

Vanessa has a data flow diagram with an item called 'Register for Class'. That item would be:

A process

Which of the following would be a "miracle" error on a DFD?

A process has no input data flows

Which of the following would be a 'black hole' error on a DFD?

A process has no output

A data flow is:

A single piece of data within a system

A process is:

An activity of a function that is performed for some specific business reason

A process is:

An activity or a function that is performed for some specific business reason

On your level 0 diagrams you have a process #3 and on your level 1 diagrams for process #3, you have processes numbered 3.1, 3.2, and 3.3. These would be called:

Children of process 3

Andrei has a diagram that shows only one process and external entities. He is developing a:

Context diagram

Amy has created a context diagram. What one DFD component is probably not shown?

Data store

Data that might be in data bases or tables that is accessed in DFD diagrams is called:

Data store

The act of taking a level 1 diagram and creating level 2 diagrams is called:

Decomposing

A process model can __________:

Document both the as-is and the to-be system

James is developing a DFD. What would be a good name for him to use on a data flow from the Calculate Federal Withholding process to a data store called YTD Payroll Data?

Federal Withholding Taxes

Ruth is an analyst. On her DFD diagram she has just placed a process. She will

Give it a verb phrase name, like 'search inventory'

On the context diagram, Tim has a process called "Start the Process". It has one output data flow 'Initial Data' and no input data flows. This is:

Incorrect in all situations

Which would be the normal order of tasks?

Interviewing and/or JAD sessions; creating use cases; creating data flow diagrams

What diagram will show all the major processes numbered 1, 2, 3, (etc.) external entities and major data stores?

Level 0 diagram

Which Data Flow Diagrams shows all the major high-level processes of the system and how they are interrelated?

Level 0 diagram

What diagram will have processes with one decimal place (like 3.1, 3.2, and 3.3) and might have flows coming in (or going out) that are not illustrated?

Level 1 diagram

What diagram will have sub-processes with numbers like 3.3.1, 3.3.2, 3.3.3 (etc) and also have flows coming in (or going out) that are not illustrated?

Level 2 diagram

Chunxia is balancing her DFD. This means she is:

Making sure that all information presented at one level is accurately represented in the next level

You have a Patient Processing data flow diagram for a hospital system. Data that is retrieved from a Patient data store includes: patient name, phone number, health insurance, HIPAA identifier, and more. In creating the level 1 diagram where you retrieve data from that data store you:

May give the data flow as 'Patient Details' instead of listing all data items

Logical process models are:

Models that describe processes without suggesting how they are conducted

Tom is trying to change his Use Case into a Data Flow Diagram. He has found that a use case step generally is the same as a ________ on the Level 1 Data flow diagram.

Process

An external entity in data flow diagramming is represented by:

Rectangles

Data stores in data flow diagramming are represented by:

Rectangles that are open on the right end

Processes in data flow diagramming are represented by:

Rounded boxes

Ramesh has drawn a set of DFD's that are not properly balanced. This is probably a:

Syntax error

The context diagram shows:

The "big picture" of the system with external entities and only one process

Mark has a data store called 'Items' and it includes all the items sold in a convenience store - sorted by UPC code with the retail price of the item. He has only one data flow called 'Item Details' that flows from the data store to the Process Checkout process. What will be true in this case?

This is correct

Carlos has a Level 0 DFD diagram where one of the external entities is the "Internal Revenue Service" - and he has a data store called "Tax Rate Table". He has drawn a data flow arrow from the Internal Revenue Service to the data store as the data has been loaded into the Tax Rate Table prior to the processing. What would be true?

This is incorrect - he doesn't need a data flow as the data was loaded into the Tax Rate Table someplace else (within the payroll system someplace, but not in this process)

Brianna has a process has two inputs but only one output.

This is normal as all processes need at least one input and at least one output

The relationship between use cases and data flow diagrams is:

Use cases tend to be developed with users to make sure the analyst has fully captured the processes and relationships; DFD's are built upon the use cases to more fully formally understand the processes involved

Data flow diagrams are:

Usually created by the project team and reviewed by users for correctness

A new patient calls up an optometrist office to make an appointment. On a DFD diagram, the new patient would be represented by:

an external entity

Which of the following is NOT correct? a) Every set of DFD's must have one context diagram b) Every process is wholly and completely described by the processes on its children DFD's c) Every process must be broken down farther on Level 1 and Level 2 diagrams d) Every data store has at least one input data flow someplace in the entire DFD system e) Every process has a unique name that is a action oriented verb phrase

c) Every process must be broken down farther on Level 1 and Level 2 diagrams