Session 11 final

Question 1

Iterative Process

Answer 1

Breaking the description of a system down into finer details
= set of charts in which one process on a given chart is explained in greater detail on another.

Question 2

Balancing

Answer 2

Conservation of inputs & outputs to a data flow diagram process when that process is decomposed to a lower level.

Question 3

What can you do to a composite data flow? (Payment & Receipt)

Answer 3

Split into separate data flows at the next level
(no new data can be added and all must be accounted for)

Question 4

What are the guidelines for drawing DFDs (5)

Answer 4

Completeness
Consistency
Timing considerations
The iterative natures of drawing DFDs
Drawing primitive DFDs

Question 5

What’s completeness

Answer 5

Extent to which all necessary components of a data flow diagram have been included and fully described

Question 6

Consistency

Answer 6

Extent to which information contained on
one level of a set data flow diagram is also included on other levels

Question 7

Timing

Answer 7

DFDs don’t do a very good job representing time

Question 8

Iterative development

Answer 8

Recognizes that requirements determination & restructuring are interacting

Question 9

Primitive DFD

Answer 9

Lowest level of decomposition

Question 10

Stop Decomposition

Answer 10

Reduced each process to a single decision/calculation
Each data store represents data about a single entity
System user doesn’t care to see any more detail
No need to split further
Each business form/transaction is shown
Separate processes for each choice on the lowest level