Modelling Logic with Decision Table
- 1. Modelling Logic with Decision Table Presentation By: Arjun Gautam
- 3. Why do we need Logic Modelling ? •What we can't represent with DFD ? • relationships among the resources, activities, outputs, outcomes, and impact for your program
- 4. What we Invest ? What we want ? What we need ? Inputs Outputs Outcomes ASSUMPTIONS What we know ? EXTERNAL FACTORS What we can't control ? Components of Logic Model :
- 7. Decision Tables • Visual Representation for specifying which actions to perform depending on given conditions . • Use in both testing and requirements management . • Dealing with complex business rules and complicated logic .
- 8. ATM •Business Rules : • Customer should have sufficient funds in their accounts . • Credit Granted
- 9. Steps to create Decision Table • Analyze the requirement and create first column • Add columns • Reduce table • Determine actions
- 10. Step 1 : Analyze the requirement Conditions Conditions Withdrawl amt<=balance Credit Granted Actions Withdrawl Granted
- 11. Step 2 : Add columns Conditions R1 R2 R3 R4 Withdrawl amt<=balance T F F F Credit Granted T T F F Actions Withdrawl Granted
- 12. Step 3:Reduce the table Conditions R1 R2 R3 R4 Withdrawl amt<=balance T F T F Credit Granted - T - F Actions Withdrawl Granted Invalid Combinations = "X" ,Infant and Senior
- 13. Step 4 :Determine cases: Conditions R1 R2 R3 Withdrawl amt<=balance T F F Credit Granted - T F Actions Withdrawl Granted T T F
- 14. Step 5 : Write test cases • Test case with R1 : balance =…200... , requested withdrawl =200, Expected result : withdrawl .....granted.... • Test case with R2 : balance =…100... , requested withdrawl = ….200. ,Expected result : withdrawl ....granted..... • Test case with R3 : balance =…100... , requested withdrawl = …200.. ,Expected result : withdrawl .....denied....
- 15. Advantages • Generate the combinations of conditions that would otherwise not have been found and therefore not tested or developed . • Requirement become much clearer .
- 16. References : • Modern SAD -Jeffery A. Hoffer • System Analysis And Design -KEC Publication • Youtube/QIO Program