title: adding 1 month to the current date in Yii
body: <p>I cannot find how to add 1 month to the current date in Yii</p>
  
  <p>I've tried  </p>
  
  <pre><code>$this-&gt;toDate = new CDBExpression('NOW()+ INSTANCE 1 MONTH');
  </code></pre>
  
  <p>but it gives me a mysql error</p>
  
  <p>check the manual that corresponds to your MySQL server version for the right syntax to use near '1 MONTH)' at line 1</p>
  
  <p>is it good to use CDBExpression or is there a better way ?</p>
  
  <p>Thank you in advance for your help</p>