var UserSchema = new Schema({
    Username: {type: String, index: true},
    Password: String,
    Email: String,
    Points: {type: Number, default: 0}
});

var User = db.model('User');
   /*
    * Function to save the points in the user's account
    */
    function savePoints(name, points){
        if(name != "unregistered user"){
        User.find({Username: name}, function(err, users){

            var oldPoints = users[0].Points;
            var newPoints = oldPoints + points;

            User.update({name: name}, { $inc: {Points: newPoints}}, function(err){
                if(err){
                    console.log("some error happened when update");
                }
                else{
                    console.log("update successfull! with name = " + name);
                    User.find({Username: name}, function(err, users) {
                        console.log("updated : " + users[0].Points);
                    });
                }
            });

        });
    }
}

savePoints("Masiar", 666);

User.findOne({Username: name}, function(err, user){
  if (err) { return next(err); }
  user.Points += points;
  user.save(function(err) {
    if (err) { return next(err); }
  });
});

User.update({ username: "faibaa" },
    { $inc: { point: 200000 } }, function(err,data){
        return res.send(data);
    });