title: How to write mongo query for the object
body: <pre><code>{
      "_id" : "WR10005",
      "_class" : "com.bioraid.mes.model.WorkOrders",
      "rountingNumber" : "R006",
      "orderId" : "MR-1017",
      "consumables" : "Chip",
      "workOrderStatus" : "pending",
      "deliveryStatus" : "on time",
      "lastCompletedStage" : "testProces",
      "dateAssigned" : ISODate("2017-02-17T05:38:57.631Z"),
      "dateCompleted" : ISODate("2017-02-17T07:53:32.680Z"),
      "opretorProcessStatus" : [ 
          {
              "opretorid" : "USER114",
              "process" : "testProces",
              "status" : "Done",
              "workCenterId" : "WC1",
              "startDate" : ISODate("2017-02-17T06:30:16.813Z"),
              "endDate" : ISODate("2017-02-17T06:42:23.237Z"),
              "qualityManagerReview" : {
                  "qaId" : "",
                  "status" : "Done",
                  "note" : ""
              }
          }, 
          {
              "opretorid" : "USER116",
              "process" : "testProces",
              "status" : "Done",
              "workCenterId" : "WC1",
              "startDate" : ISODate("2017-02-17T06:30:16.813Z"),
              "endDate" : ISODate("2017-02-17T06:42:23.237Z")
          }
      ],
      "workOrdersRouting" : {
          "testProces" : [ 
              {
                  "routingStep" : "R006*010",
                  "operationName" : "Operation1",
                  "operationStatus" : "Completed",
                  "operationResult" : "Pass",
                  "operationNote" : "test"
              }, 
              {
                  "routingStep" : "R006*020",
                  "operationName" : "adalks",
                  "operationStatus" : "Completed",
                  "operationResult" : "Pass",
                  "operationNote" : "sddsdfsf"
              }
          ],
          "Embossing" : [ 
              {
                  "routingStep" : "R006*030",
                  "operationName" : "Water Cleaning",
                  "operationStatus" : "",
                  "operationResult" : "",
                  "operationNote" : ""
              }
          ],
          "Turbidity" : [ 
              {
                  "routingStep" : "R006*040",
                  "operationName" : "Embossing Assembly",
                  "operationStatus" : "",
                  "operationResult" : "",
                  "operationNote" : ""
              }
          ]
      }
  }
  </code></pre>
  
  <p>I want to get <code>{'opretorProcessStatus.qualityManagerReview.status' : {$ne : null}}</code> but this is not giving proper result can any one help me to write this.</p>
  
  <p>and other one is <code>db.getCollection('workOrders').find({'opretorProcessStatus.qualityManagerReview.status' : "Done"})</code>.</p>