title: How to filter the result that include null value in the query?
body: <p>Hallo, I have a table which have the following item:</p>
  
  <pre><code>CODE UPDATE_DT
  ---- ---------
  APP  08-APR-11
  REJ  null
  CAN  null
  </code></pre>
  
  <p>If I have to filter it by date, lets say for this month, 1-APR-2011 to 30-APR-2011. The output of the query will be like following:</p>
  
  <pre><code>CODE UPDATE_DT
  ---- ---------
  APP  08-APR-11
  </code></pre>
  
  <p>Is it possible for me to select query result that could include null value just like the table locate at the top most of this question?</p>
  
  <p>THanks @!</p>