Topic 1.3 Systems Development & Documentation Techniques Flashcards
What is a documentation
- a set of documents and models
- narratives, data flow models, flowcharts
- describe who, what, why, when, where of systems
- input, process, storage, output and controls
What do data flow diagrams follow
- Data source/ destination
- data stores
- processes
Four basic elements and shapes of DFD
= data store
-> data flow
O processes
Square entity
What does the entity (square) represent in a data flow diagram
- the source of the data or the input
- represents the destinations output of the destination
What does the data flow (->) show
The movement of data between:
- processes
- entities
- data store
The arrow should label what is moving
What does the process represent in the DFD
The process represents the transformation of data
What does the data store (=) represent
The data at rest
What are the 3 levels of data flow diagrams
Context
Level-0
Level-1
What does the context diagram involve
Highest level (summary form) Purpose: show inputs and outputs into system Characteristics: one process symbol only, no data stores
What does a level 0 data flow diagram include
Purpose: show all major activity steps of a system
Characteristics: processes are labelled 1.0, 2.0 etc
What does a level 1 data flow diagram include
Purpose: show one major activity divided into sub activities
Characteristics: processes are labeled 1.1, 1.2 etc
What do flow charts show?
- Use symbols to logically decipher transaction processing and the flow of data through a system
- Use pictures or symbols to explain
What are the 3 types of flowcharts
- document
- system
- program
What does the document flowchart involve?
- Shows the flow of documents and data for a process
- useful in evaluating internal controls
What does the document flowchart show
- Tells us who is doing what, very good when you are evaluating internal control
- start in top left and go down to bottom right
- shows everything from cradle to grave
- can highlight where there are weaknesses and inefficiencies. Unnecessary complexities