title: Getting a "not a single-group group function" error, tried researching it
body: <p>I'm taking a database summer course so I'm new at this. Here is my code. I'm trying to display the average price for each type of book in my database. </p>
  
  <pre><code>SELECT DISTINCT type, AVG(price) AS AVERAGE_PRICE
  
  FROM book
  
  ORDER BY type;
  </code></pre>