SQA Advanced Higher Computing Science

## What analysis produces Analysis is the first stage of development, and it happens before anything is designed. Its job is to decide what problem is being solved and what a solution has to do, so that design, implementation and testing all have something fixed to be checked against. The same analysis applies whether the solution is a program, a database or a website, and at Advanced Higher a project usually joins two or all three of these together. A problem is first described by its **purpose**, a short statement of why the system exists and who it is for. The purpose is then broken down by asking three questions about the system. | Question | What it identifies | Example for a library loan system | |---|---|---| | What goes in? | The **inputs**: the data the system receives, and from whom | Member number, book barcode, return date | | What has to be done to it? | The **processes**: calculations, comparisons, searches, updates | Check the member has no overdue items, work out the due date, update the book's status | | What comes out? | The **outputs**: what the system displays, prints, sends or stores | A loan receipt, a list of overdue items, an updated record | Listing inputs, processes and outputs does not say how anything will be done. It says what the system has to handle, and a missing item at this stage is cheap to fix whereas the same omission found during testing means redesign. ## The requirements specification A **requirements specification** is the document…