title: Use Yii2's Autocomplete widget to query more than one table
body: <p>Yii2's Autocomplete widget makes it very easy to implement an autocomplete user input field, but the widget's parameters only accept one data model.</p>
  
  <p><a href="http://www.yiiframework.com/doc-2.0/yii-jui-autocomplete.html" rel="nofollow">http://www.yiiframework.com/doc-2.0/yii-jui-autocomplete.html</a></p>
  
  <p>I need the autocomplete to query 2 data models (or 2 tables in the database) when trying to auto-populate the user's entry.</p>
  
  <p>Do I have to make my own custom autocomplete functionality? Or is this possible with Yii2's widget?</p>