title: how to check if any of the value in a column is null it shld count value 1 in mongoose?
body: <p>how  to check if any of the value in a column is null it shld count value 1 in mongoose?
  i tried</p>
  
  <pre><code>data: {
                          $max: {
                              $cond: [{
                                  $or: [{ $eq: ["$mycolumn", null] },
                                      // { $eq: [ "$anotherField","value"] }
                                  ]
                              },
                                  0,
                                  1]
                          }
  
                 },
  </code></pre>
  
  <p>but this is returning null.how to fix this?Thanks in advance</p>
  
  <p>my collection is </p>
  
  <pre><code>
  { _id: 1, item: null ,name:sam,status:open},
  { _id: 2, item: null ,name:arun,status:open},
  { _id: 2, item: 1,name:arun,status:close},
  { _id: 2, item: 1,name:sam,status:close},
  
  
  </code></pre>
  
  <p>also i have to retrieve by grouping status.</p>