title: mongodb aggregate skip limit count for pagination
body: <p>I want to apply the pagination on this aggregated data (all the documents which matched and project with both collection 2 and 3). I have tried multiple 
  queries, i am passing limit 25 but it will get only 20 document, which changes require in this query for pagination</p>
  
  <pre><code>var pipeline = [{
          $match: query
      }, {
          $limit: limit
      }, {
          $skip: skip
      }, {
          $lookup: {
              from: "collection2",
              localField: "collection1Field",
              foreignField: "collection2Field",
              as: "combined1"
          }
      }, {
          "$unwind": "$combined1"
      }, {
          $lookup: {
              from: "collection3",
              localField: "collection1Field",
              foreignField: "collection3Field",
              as: "combined2"
          }
      }, {
          "$unwind": "$combined2"
      }, {
          $project: {
              "collection1Field1": 1,
              "collection1Field2": 1,
              "collection1Field3": 1,
              "collection2Field.field1": 1,
              "collection2Field.field2": 1,
              "collection3Field.field1": 1,
              "collection3Field.field2": 1,
          }
      }
  ];
  </code></pre>