Why do we need the design phase?
Before you start developing a system you need a plan of action, together with design ideas for each of the areas of the system. Spending a good amount of time designing a system in advance will allow you and the rest of the development team the ability to solve problems in advance of the development, saving a considerable amount of time and money. It may also highlight issues that need to addressed before the project can move ahead.
What things need designing?
- Form and Input Screen Designs
- Report and Output Screen Designs
- Input validation the needs to performed on data.
- Data Structures that need to be created
User documentation is required to assist the user in using the system. The documentation can be paper or electronic based and can include:
- Training Manuals
- Operating procedures to be followed when using the system.
- Video tutorials
Technical documentation is designed to help maintain and upgrade the system.
Technical documentation may include:
- Software documentation, indicating the names and purpose of functions in the code.
- A system map, showing how all the different parts of the system fit together.
- Data validation and the validation ranges for different data.
Engineers or system administrators will refer to this documentation when they are looking at the system.
Screens, Forms & Input
In your exam you will likely be asked to design a screen input form.
In order to succeed you need to ensure that you include:
- A screen title
- Appropriate inputs & labels
- Appropriate annotations explaining the purpose of each and any validation required.
- A submit button
It should also:
- Be sensibly laid out
- Use the full area of the screen appropriately
There are three types of data that may be entered in to a system:
- This is data that fits comfortably within the acceptable data range (Age input: 25)
- In this instance the system would normally accept the data without further question.
- This is data that sits at the very edge of acceptable data. ( Age input : 0 or 110)
- In this instance the system should normal prompt for the user to double check the data (Are you sure….)
- This is data that is outside acceptable data range (Age input: -45 Â or 20000 )
- In this instance the system should reject the data, requiring the user to input a valid answer.