title: Is it possible to store '' (empty string) as a non NULL value in the database?
body: <p>I am using Oracle DB. At the database level, when you set a column value to either NULL or '' (empty string), the fetched value is NULL in both cases. Is it possible to store '' (empty string) as a non NULL value in the database?</p>
  
  <p>I execute this </p>
  
  <pre><code>UPDATE contacts SET last_name = '' WHERE id = '1001';
  
  commit;
  
  SELECT last_name, ID FROM contacts WHERE id ='1001';
  
  LAST_NAME                  ID
  ------------               ------
  null                       1001
  </code></pre>
  
  <p>Is it possible to store the last_name as a non-NULL empty string ('')?</p>