求助： mongoose 中 update 用 save 修改失效，是什么原因？

[NELSONCHI]

var mongoose=require('mongoose');
var db=mongoose.connect('mongodb://localhost/words');
var wordSchema=require('./word_schema.js').wordSchema;
var Words=mongoose.model('Words',wordSchema);
mongoose.connection.once('open',function(){
  var query=Words.findOne().where('word','book');
  query.exec(function(err,doc){
    console.log('is document new? '+doc.isNew);
    console.log('\nbefore save:');
    console.log(doc.toJSON());
    doc.set('word','Book');
    doc.set('first','B');
    console.log('\nmodified fields:');
    console.log(doc.modifiedPaths());
    doc.save(function(err,res){
      console.log(res);
      mongoose.disconnect();
      // Words.findOne({word:'Book'},function(err,res){
      // console.log('\nafter save:');
      // console.log(res);
      // mongoose.disconnect();
      // });
    });
  });
});

数据库： https://github.com/CHINQ/angularnodemongodb/blob/master/mongodb/data/generate_data.js word_schema.js ： https://github.com/CHINQ/angularnodemongodb/blob/master/mongodb/word_schema.js

[Mirachael]

Model.update(query, update, {new: true}, function(err, result) {})

new: true 表示返回修改后的值

[forl]

看下这个问题：
http://stackoverflow.com/questions/22278761/mongoose-difference-between-save-and-using-update