Process Decomposition Techniques for system modeling Functional Decomposition

Process Decomposition Techniques for system modeling

Functional Decomposition Functional decomposition is used to design large transaction type systems in which the process sequence is determined by the computer l Hierarchy Charts l Data Flow Diagrams l IPO analysis

Registration Problem Students register for OU classes at UCT by determining classes from the catalog with advice from program and staff advisors. Once classes start students attend classes and prepare assignments. At the end of the semester the professor assigns grades and reports results to the University.

Hierarchy Charts Hierarchy charts are used to identify the major functions that a system must perform, next identify major subfunctions, etc. Hierarchy charts can also include input and output variables.

Hierarchy Chart l l l Register for Class » Review Catalog » Consult Program Advisor » Consult UCT Advisor Take Course » Attend Classes » Prepare Assignments Generate Grades » Assign Grades » Report Results

Data Flow Diagram Context (Level 0) Students Schedules Requests Advice Registration System Advisors Grades Work OU Admin

Data Flow Diagram Level 1 Students Requests 1. Register for Class Schedules Work 2. Take Course St Advice Classes Test_Results D 1 Classes Roster D 2 Students Advisors 3. Generate Grades D 3 Rolls Roster Grades OU Admin

Entity Relationship Diagram Classes Students Rolls