title: Hidden condition to all possible queries
body: <p>I'd like to hide selecting objects not by rewriting all SQL queries but by more simple way.</p>
  
  <p>So, I'd like to add a rule (or something else) to a database for a particular table. E.g. if we delete a user from a website we execute something like the next:</p>
  
  <pre><code>UPDATE user_common SET is_deleted='t' WHERE user_id=1234
  </code></pre>
  
  <p>And there are no need to rewrite all existing queries about users, the condition is hidden:</p>
  
  <pre><code>SELECT first_name, second_name FROM user_common WHERE coins&gt;200
  </code></pre>
  
  <p>The SELECT above will be executed with a hidden condition, e.g.:</p>
  
  <pre><code>SELECT first_name, second_name FROM user_common WHERE coins&gt;200 AND is_deleted!='t'
  </code></pre>
  
  <p>How to make it working?</p>