Which of the following answers are part of a well-structured relational database? Select all that apply. All tables must have a foreign key All non-key attributes must describe the enitity contained...

Which of the following answers are part of a well-structured relational database? Select all that apply. All tables must have a foreign key All non-key attributes must describe the enitity contained in the table All tables must have a primary key that is unique All transaction tables must have Date as a non key attribute All attributes must be single valued All of the above are correct None of the above are correct