title: Big Query cache
body: <p>I have three questions related to <a href="https://cloud.google.com/bigquery/querying-data#query-caching" rel="nofollow noreferrer">BigQuery's cache</a>, as the ability to get results from cache greatly reduces costs on large queries.</p>
  
  <ol>
  <li><p>If the data has not been modified, is there a way to extend the cache longer than the default of ~24 hours. For example, what if I have a static dataset that hasn't been changed in 6 months?</p></li>
  <li><p>Is there a way to retrieve results from cache if there have been subtle changes on the query that doesn't affect what information it is retrieving? For example:</p>
  
  <ul>
  <li><code>SELECT first_name, last_name FROM mytable</code> vs <code>SELECT last_name, first_name FROM mytable</code> (ordering)</li>
  <li><code>SELECT id, last_name FROM mytable</code> vs <code>SELECT id, last_name AS last, FROM mytable</code> (alias)</li>
  <li><code>select id from table</code> vs <code>SELECT id FROM table</code> (caps)</li>
  </ul></li>
  <li><p>Is cache automatically invalidated if the data-set is modified? If not, is there a way to manually invalidate all cache for that table?</p></li>
  </ol>