title: Mongo sort by single enum and other field
body: <p>On my collection I have the fields:</p>
  
  <pre><code>{
    ...
    status: ['scheduled', 'sent', 'error']
    sendDate: Date()
  }
  </code></pre>
  
  <p>My objective is to show the <code>scheduled</code> first, and then the <code>error</code> and <code>sent</code> sorted by <code>{ sendDate: -1 }</code>. I would do 2 queries, but I want to keep it paginated. Because of different timezones, the <code>sendDate</code> might end up as <code>scheduled</code> before other that are already <code>sent</code>. Like:</p>
  
  <pre><code>{
    id: 1,
    sendDate: ISODate("2019-06-11T19:28:50.617Z"),
    status: 'scheduled'
  }, {
    id: 2,
    sendDate: ISODate("2019-06-12T19:28:50.617Z"),
    status: 'sent'
  }, {
    id: 3,
    sendDate: ISODate("2019-06-10T19:28:50.617Z"),
    status: 'scheduled'
  }, {
    id: 4,
    sendDate: ISODate("2019-06-10T19:28:50.617Z"),
    status: 'sent'
  }, {
    id: 5,
    sendDate: ISODate("2019-06-11T19:28:50.617Z"),
    status: 'error'
  }
  </code></pre>
  
  <p>The expected sorted id's would be: </p>
  
  <pre><code>{
    id: 1,
    status: 'scheduled'
  },{ 
    id: 3,
    status: 'scheduled'
  },{ 
    id: 2,
    status: 'sent'
  },{ 
    id: 5,
    status: 'error'
  },{ 
    id: 4,
    status: 'sent'
  }
  </code></pre>