7) What problem do you expect it to solve? What caused the need for this project?
If the effort to create a database is going to be expended, then somebody finally got fed up with doing things without one. To make the database solve this problem, you need to understand what the problem is, and what is driving the expenditure of resources (money, time, etc.) to do this project.
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This is very similar to question 4, but in my opinion needs to be asked separately. These two questions are the most important IMHO, but for some reason, customers are often reluctant to provide this info. This is why I ask it as two separate questions.
The reason I feel knowing the problem is more important that knowing what they want it to do is that they will blame you and your database if it doesn't solve their problem, even if it does everything they asked. Part of your job is to determine if what they are requesting will actually solve their problem.
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