node.js – 使用find通过引用查找的MongooseJS

var mongoose = require ('mongoose'),dev      = require ('../db').dev ();

var schema = new mongoose.Schema ({
  date: {
    type: Date,default: Date.Now
  },company: {
    type: mongoose.Schema.Types.ObjectId,ref: 'Company'
  },questionnaire: {
    type: mongoose.Schema.Types.ObjectId,ref: 'Questionnaire'
  }
});

module.exports = dev.model ('Survey',schema);

我只想查找具有特定公司ID的调查.我怎么做？我试过(使用我的Express处理程序)：

app.get ('/survey',function (req,res) {
  Survey.find ({ company: req.query.company }).populate ('questionnaire').exec (function (err,surveys) {
    return res.json (surveys);
  });
});