title: Grails efficient hasMany-Relationship in View
body: <p>I'm saving contacts (email, mobile phone, ICQ, AIM etc.) for people like this:</p>
  
  <pre><code>class Person {
    static hasMany = {
      contacts: Contact
    }
  }
  class Contact {
    String code
    ContactType type
  }
  class ContactType {
    String name
  }
  </code></pre>
  
  <p>In my view, I've written some Templates for displaying each contact with a select-box for the contact-type and a textfield for the code, spiced up with some JavaScript for adding and deleting.</p>
  
  <p>My question is: Is there an easy and elegant way to update the data similar to <code>personInstance.properties = params</code> or do I have to read out all the fields, deleting removed, updating changed and adding new ones?</p>