title: How to ref to multiple models mongoose mongodb
body: <p>I have 3 models MonthlyMenu. FrozenFood, and DailyDeal.</p>
  <p>I'm creating an order model where inside the item field I want to have the id of item which will be from one of the above models.</p>
  <p>How can I ref to multiple models in a mongoose schema?</p>
  <pre><code>item: {
    type: mongoose.Schema.Types.ObjectId,
    required: true,
    ref: 'DailyDeal',
  },
  </code></pre>