Just wondering is it possible not to read all values in database file, e.g. magicCookie, record length, etc. and just assume an offset into the actual file content since we know the schema and the actual file format or does 1 have to implement and return all file content and headers in file? Or would 1 automatically fail if didn't implement this?
You could hard-code the position where the records section starts (and maybe document this decision). Because the assignment has no must requirement about having to read the database schema, you certainly won't fail taking such an approach. Maybe you will lose some points, because this approach is not really flexible for future changes (like columns getting bigger, smaller, being added, removed,...)
I agree with the Roberto and Roel, I don't think your approach would automatically fail but I'd be surprised if you didn't lose some marks, as I'm not sure how you could justify not checking the magic cookie, it's there to check you are opening file in the correct format, i.e. what would happen if didn't check the magic cookie and tried to open a Word document for example.
I definitely agree with keeping it simple, but not to the extent where I cannot reasonably justify implementing functionality.