title: Oracle view invalid identifier
body: <p>I have to implement </p>
  
  <blockquote>
    <p>Create a view that shows the total rental income per movie in the database</p>
  </blockquote>
  
  <p>So I did</p>
  
  <pre><code>CREATE OR REPLACE VIEW MovieIncome AS SELECT s.movie_copy_id, SUM(S.PRICE)
  AS Income FROM TRANSACTIONS s
  left OUTER JOIN MOVIE_COPIES ON MOVIE_COPIES.movie_copy_id = s.movie_copy_id
  left OUTER JOIN MOVIES ON MOVIES.ID = MOVIE_COPIES.MOVIE_copy_id
  WHERE MOVIES.ID = MOVIE_COPIES.MOVIE_copy_id
  GROUP BY MOVIES.NAME;
  </code></pre>
  
  <p>Transactions table have: transaction_id, movie_copy_id, customer_id, price. <br>
  MOVIE_COPIES table have: type, store_id, movie_copy_id, movie_number<br>
  MOVIES table have: id, name, minutes.<br></p>
  
  <p>But Oracle drops me </p>
  
  <p><code>ORA-00904: "S"."MOVIE_COPY_ID": invalid identifier</code></p>
  
  <p>My friend has same task, and his columns are different name, but same purpose and works fine, for me it doesn't.</p>