Process-Oriented Analysis
Conceptual Foundation
- System Model: we need a feedback to eliminate the entropy
Structured System Analysis
- A context defines a setting or environment.
- Context Diagram AKA DFD Level 0
- Data Flow Diagram (DFD)
- Decomposed DFD (Lower Level) of Process 1.0
- Data Dictionary
Structured System Analysis Activities
These are the steps to follow for analyzing a structure system:
- Develop a context diagram
- Define the boundaries (i.e., scope) of the application. Specifically, define what the application will do and what it will not do. Draw the circle identifying the application and write the application name in the center.
- Using the application boundary as a starting point, identify all external entities with which the application must interact. For each entity, draw one square on the diagram and label the square.
- For each entity, create a definition in the data dictionary.
- For each external entity, identify the specific data flows that define the interface.
- For each data flow, create a definition and list of tentative contents in the data dictionary.
- Develop a set of balanced data flow diagrams: There are 2 types of DFDs:
- Logical DFD:
- Focus on what happens in a particular information flow
- logical DFD doesn’t delve into the technical aspects of a process or system, such as how the process is constructed and implemented
- Non-technical employees should be able to understand these diagrams
- Physical DFD
- focus on how things happen in an information flow.
- A detailed physical data flow diagram can facilitate the development of the code needed to implement a data system.
- Develop a data dictionary
- Optionally, develop a state-transition diagram if building an on-line or real-time application
Process-Oriented Design
Structure Chart
In all methods of documentation, the starting point is a structure chart
Read more about moving between the DFD levels from this page https://www.lucidchart.com/pages/data-flow-diagram
Resources
