title: PostgreSQL: performance of select null vs false
body: <p>In PostgreSQL (v9.4) with a big table (> 10M rows), is there any difference in the performance (speed) of these two queries?</p>
  
  <ol>
  <li>Select all entries with a <code>null</code> value in a <code>bigint</code> column.</li>
  <li>Select all entries with a <code>false</code> value in a <code>boolean</code> column.</li>
  </ol>
  
  <p>Also, would it make any difference if query number 1 was performed on a <code>varchar</code> column?</p>
  
  <p>Thanks!</p>