How to add key in along with array object in node js
<p>Here is my a resultant array and now I want to add extra key along with <strong>current</strong> key.
tried .<strong>push is not a function</strong></p>

<pre><code>aa[0]['new_key'] = 'blah';    // is not working
</code></pre>

<p>My array is looks like.</p>

<pre><code> var aa =  [
        {
          "main": "56d940bb2b5916181d0906e2",
          "current": 6544
        }
      ]
</code></pre>

<p>And my original code is using mongoDB query.</p>

<pre><code>connection.modal.find( { 'user_id' : user_id }, { 'abc.def' : true}, function ( err, result ) {

            if ( !err ) {

                if( result.length ) {

                    result[0]['abc'].def[0]['new_key']  = 'blah';
                    response['success'] = true;
                    response['result'] = result[0]['abc'].def;
                    response['msg'] = 'data fetch';
                    res.json(response);
                } else {

                    response['success'] = false;
                    response['result'] = '';
                    response['msg'] = 'No record found';
                    res.json(response);
                }
            } else {

                response['success'] = false;
                response['result'] = '';
                response['msg'] = 'Error';
                res.json(response);
            }
        });
</code></pre>