I'm trying to make short way for me. I want to create one function for all queries. For settings.amount, settings.balance etc..
exports.updateUsers = function ( user_id, where, what, pass )  {
    var _where = 'settings.'+where; //when I use it doesn't update
    user.findOneAndUpdate(
          {'user_id' : user_id}, 
          {_where : what }).exec(function(e,d){
            pass("ok")
          })
};
How can I achive my want? Are there any way?
 
     
    