title: Adding data before save in CakePHP
body: <p>Post hasMany Tag:
  My form:</p>
  
  <pre><code>$form-&gt;input('Post.title');
  ...
  $form-&gt;input('Tag.0.name'); //1st tag
  $form-&gt;input('Tag.1.name'); //2nd tag
  </code></pre>
  
  <p>This works perfectly, but...</p>
  
  <p>I create some fields <code>Tag.n.name</code>, and I want add each time one tag by <code>$this-&gt;data['Tag'][some_number]['name'] = 'all';</code><br>
  Do not ask me why i want that, but tell me how i can add 'all' tag in my model to each Post?</p>
  
  <p>This should get effect 4 INSERT sqls: one add post, and three: 1st tag, 2nd tag, all tag.</p>
  
  <p>More explain: How add more tags without form fields? How add default tags? No input hidden, only pro solutions:)</p>