Convert String to Date by using map function in MongoDb

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Convert String to Date  by using map function in MongoDb



db.getCollection('trackings').find({"created_date": /^Fri Dec 11 2015.*/})
      .map(
        function(tracking) {
          db.getCollection('trackings').update({ "_id": tracking._id}, 
          {
            $set: {
                "created_date": new Date(tracking.created_date)
            }
          }, 
          {
            multi: false
          }
      );
     return [tracking.created_date]
    }
   );

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