猫鼬只插入ID

猫鼬只在我的数据库中插入ID。如果我调试代码，则product_data已填写，但Product为空。那怎么可能？

var ProductSchema = require('./../models/productSchema');
var Products = mongoose.model('Product',ProductSchema);
[...]
    for(var i=1; i<result.length;++i){
      var product_data = {
          CNK : "TODO",
        EAN : "TODO",
        name : {nameNL: result[i]["product_name"], nameFR: "TODO"},
      [...]
         }
        Product = new Products(product_data);
        console.log(Product);
        Product.save(onInsert(err));
}

productschema.js

var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var ProductSchema = new Schema({
    _id: Number,
    CNK:String,
    EAN:String,
    name:{nameNL:String,nameFR:String},
   [...]
    }

});