Unit test code that interacts with database without creating data in database

Question

I want to test my C# code in Visual Studio with unit tests. The code interacts with a MySQL database.

An example of what I want to test
A user opens my application and will be saved in the database via a webservice. Now I want to know if the table Users has one more row before the new user came. But if I test the method in the webservice, which will create a record in the database, test data will be in the database. And I don't want test data in my database.

Is there a solution for this problem?

Answer 1

I think what you're looking for is mocking. This allows you to simulate your data access code in order to test your business logic.

There are lots of good frameworks out there including moq and rhino mocks.

If you want to actually populate your database in order to test your data access layer then you're looking for more of an integration test. I've written quite a thorough answer covering my approach to db integration tests here.

Answer 2

What you are looking for is a Mock. For example Moq for C#.

Wrap your database logic in an interface and mock it in your unit test. That way you can interact with the mocked database logic, without really executing it.