The point of mocking the DB isn’t to avoid hassle, it’s to not test your dependencies. Technically the calling code might not even know it’s a DB, and it might not even care, or it might be a DB sometimes or an API other times, or even a command line once in awhile. They are only tightly coupled if you write it that way. And yes, we would be disinterested in the schema and query errors we might catch because that’s not the point of the test.
