title: How do you negate a $match aggregate in mongodb
body: <p>I have the following query that I need to find the reverse. </p>
  
  <pre><code>db.contracts.aggregate([ 
      { $match: { currentBalance: { $gt: 0 }, status: 'open' } }, 
      { $project: { customer_id: 1, lastTransactionDate: 1, currentBalance: 1, status: 1 } }
  ])
  </code></pre>
  
  <p>I an trying not to use </p>
  
  <pre><code>$or: [ currentBalance: { $ne: 0 }, status: { $ne: 'open' } ]
  </code></pre>
  
  <p>What I would really like is to use <code>$not: [ condition ]</code> as I will have more difficult aggregations to write. However I cannot find the right syntax. Any help appreciated. I am using mongodb 3.0.7</p>