title: What does the filtering attributes on the CRM 2011 plugin registration tool do?
body: <p>I assumed that for an Update plugin, it specified a list of attributes, that if are changed, cause the plugin to fire.</p>
  
  <p>So if I register a plugin against <code>Foo</code>, with only one filtering attribute specified against <code>Bar</code>, every time a <code>Foo</code> entity is updated, CRM performs a check to see if <code>Bar</code> has been updated, if it has, it runs my plugin.  So with the code below, I would expect my plugin to execute once.</p>
  
  <pre class="lang-cs prettyprint-override"><code>Foo foo = new Foo();
  foo.Bar = 0;
  foo.Id = service.Create(foo);
  foo.Bar = 1;
  service.Update(foo.Bar); // My plugin would execute
  service.Update(foo.Bar); // Bar hasn't changed, I would assume the plugin will not  execute
  </code></pre>
  
  <p>Am I right in this assumption?</p>