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Which dependency causes the repetition?

The situation

A college library keeps everything in one table:

Loan(issue_id, book_isbn, book_title, author_name, author_country, member_id, member_name, member_dept, issue_date, due_date)

What is true about the data:

  • issue_id is unique for every loan
  • one ISBN is always one title, by one author
  • one author has one country
  • one member has one name and one department
  • the same book can be borrowed many times, by different members

The librarian reports three problems. Corrections to an author's country have to be made in many rows. A newly acquired book that nobody has borrowed cannot be recorded at all. And when the last loan of a book is deleted, the book's details disappear from the database.

The author's country is repeated in every row for every loan of every book by that author.

Which functional dependency is responsible?