title: Select name for authors that havent written a book
body: <p>We have to select authors that havent written a book but there are 3 different tables which makes me confused about how to write the join expression. </p>
  
  <p>We have tables:</p>
  
  <pre><code>authors: author_id
  authorships: author_id, book_id
  books: book_id. 
  </code></pre>
  
  <p>Obviously I selected the names from authors and tried inner join but it wont work for me. Help would be appreciated!</p>