ISDS 4125 Ch 5

Charon 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

Data flow diagramming is:

Focused on the processes or activities that are performed

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

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

Which would be the normal order of tasks?

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

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

Context Diagram

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

Context Diagram

An external entity is:

A person, organization or system outside of the system

A data flow is:

A single piece of data

A process is:

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

Decomposing a DFD means:

Breaking complex processes into a structured set of detailed diagrams

A process model can __________:

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

What are some characteristics of DFD's?

Every process is wholly and completely described by the processes on its children DFD's Every set of DFD's must have one context diagram Every process has a unique name that is an action oriented verb phrase Every data store has at least one input data flow someplace in the entire DFD system

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

Artemis is balancing her DFD. This means she is:

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

Logical process models are:

Models that describe processes without suggesting how they are conducted

Bacchus 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

Hermes 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)

Medusa 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

Hera 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 'black hole' error on a DFD?

A process has no output