Structured Methodology and COBOL

1. Structured Methodology and COBOL

2. OUTLINE OF CLASS • Discussion • Structured Analysis and Design • Structured Programming (COBOL) • Systems Analysis Strategies • Group Project

3. Strategies for Systems Analysis and Problem Solving • Modern Structured Analysis • Model • Model-driven development • Process Models - Data Flow Diagrams (DFDs)

4. Structured Systems Analysis and Design Methodology (SSADM) • A systems approach to the analysis and design of information systems. • Involves the application of a sequence of analysis, documentation and design tasks. • Uses a combination of text and diagrams throughout the whole life cycle of a system design, from the initial design idea to the actual physical design of the application.

5. SSADM (cont.) • SSADM uses a combination of three techniques: • Logical Data Modeling • Data Flow Modeling • Entity Behavior Modeling

6. Structured programming • A subset or subdiscipline of procedural programming, one of the major programming paradigms. It is most famous for removing or reducing reliance on the GOTO statement (also known as "go to"). • Break larger pieces of code into shorter subroutines (functions, procedures. methods, blocks, or otherwise) that are small enough to be understood easily.

7. COBOL • COBOL is a third-generation programming language. Its name is an acronym, for COmmon Business Oriented Language, defining its primary domain in business, finance, and administrative systems for companies and governments. • COBOL did not support local variables, recursion, dynamic memory allocation, or structured programming constructs. Support for some or all of these features has been added in later editions of the COBOL standard.

8. Structure of COBOL (Example) • Handout

9. Structure Chart

10. What is System Analysis? • Systems analysis is the dissection of a system into its component pieces for purposes of studying how those component pieces interact and work. • Systems analysis is (1) thesurvey and planning of the system and project, (2) the study and analysis of the existing business and information system, and (3) the definition of business requirements and priorities for a new or improved system. A popular synonym is logical design.

11. The Survey Phase • Survey Problems, Opportunities, and Directives • Negotiate Project Scope • Plan The Project • Present The Project

12. Outputs of Survey Phase • Project Charter • Problem Statement • Scope Statement

13. The Study Phase • Model the Current System • The overriding modeling strategy is information hiding. • Data, Process, and Geographic Modeling • Analyze Problems and Opportunities • cause/effect analysis.

15. The Study Phase (cont.) • Establish System Improvement Objectives and Constraints • Modify Project Scope and Plan • Present Findings and Recommendations

17. The Definition Phase • Outline Business Requirements • Model Business System Requirements • Logical models depict what a system is, or what a system must do – not ‘how’ the system will be implemented. Because logical models depict the essence of the system, they are sometimes called essential models

18. Model Business System Requirements • Data Modeling • Process Modeling • Geographic Modeling (Network Modeling) • Object Modeling

19. The Definition Phase (cont.) • Build Discovery Prototypes (opt.) • Prioritize Business Requirements • Timeboxing is a technique which develops larger fully functional systems in versions. • Modify the Project Plan and Scope

20. Deliverables • Business Requirements Statement • “Big Picture” of the system • Trigger of the systems design

21. Group Project • Objectives • Milestone 1 (if not done yet) • Milestone 2 • Overviews • Problem Statement • Narrative descriptions of processes (data flows, data stores, external entities)