mongoose find nested object by id code example

Example 1: mongoose nested object without id

var subSchema = mongoose.Schema({
    //your subschema content
},{ _id : false });

Example 2: mongoose find by nested property

System.findOne({ 'nodes.main.Alpha': 23000}, function(err, system){
   if(err){console.log(err);}
   else{console.log(system);}
 });