npm install mongoose

 var mongoose = require("mongoose");
 var Schema = mongoose.Schema;
 var db = mongoose.connection;
 mongoose.connect('mongodb://localhost/animal');
 db.on('error', console.error);
 db.once('open', function() {
  //这里建立模式和模型
 }

 //这里建立一个动物的模式，所有动物都拥有这个模式下的所有属性
 var animalSchema = new Schema({
  name: String,
  age: Number,
 });

 var animalMode = db.model('Animal', animalSchema);

 var cat = new animalMode({
  name: 'catName',
  age: '7', //这里依然使用字符串，mongoose会自动转换类型
  });

 cat.save(function(err, thor) {
  if (err) return console.log(err);
  console.log(thor);
 });
 //或者可以使用create
 //cat.create(function(err, thor) {
 // if (err) return console.log(err);
 // console.log(thor);
 //});

 //执行查找
 animalMode.find(function(err, people){
  if(err) console.log(err);
  console.log(people);
 });
 //查找符合条件数据
 animalMode.findOne({title: 'catName'}, function(err, cat){
  if(err) console.log(err);
  console.log(cat);
 });

 var animalMode = mongoose.model('Animal', schema);

 var cat = new animalMode;
 cat.name = 'Statue of Liberty'    //String
 cat.age = '7';        //Number
 cat.updated = new Date;      //Date
 cat.binary = new Buffer(0);     //Buffer
 cat.living = false;       //Boolean
 cat.mixed = { any: { thing: 'i want' } }; //Mixed    
 cat._someId = new mongoose.Types.ObjectId; //ObjectId
 cat.ofString.push("strings!");    //Array

 var animalSchema = new Schema({any: {}});
 var animalSchema = new Schema({any: {Schema.Types.Mixed}});

 var animalSchema = new Schema({
  name: String,
  age: Number,
 });

 animalSchema.methods.findSimilarTypes = function (cb) {
  return this.model('Animal').find({ name: this.name }, cb);
 }

 var animalMode = db.model('Animal', animalSchema);

 cat.findSimilarTypes(function(err, cat){
  if(err) console.log(err);
  console.log(cat);
 });

 animalSchema.statics.findByName = function (name, cb) {
  return this.find({ name: new RegExp(name, 'i') }, cb);
 }
 var animalMode = db.model('Animal', animalSchema);

 animalMode.findByName('catName', function (err, animals) {
  console.log(animals);
 });

 var animalSchema = new Schema({
  name: String,
  age: Number,
  tags: { age: [String], index: true } // field level
 });

 animalSchema.index({ name: 1, age: -1 }); // schema level

 animalSchema.set('autoIndex', false);
 // or
 new Schema({..}, { autoIndex: false });

 cat.save(function(err, thor) {
  if (err) return console.log(err);
  console.log(thor);
 });
 //或者可以使用create
 cat.create(function(err, thor) {
  if (err) return console.log(err);
  console.log(thor);
 });

//find
animalMode.find(function(err, cat){
 if (err) console.log(err);
 console.log(cat);
})

//findOne
animalMode.findOne({name: 'catName'}, function(err, cat){
 if (err) console.log(err);
 console.log(cat);
})

//findByID
//与 findOne 相同，但它接收文档的 _id 作为参数，返回单个文档。_id //可以是字符串或 ObjectId 对象。
animalMode.findById(id, function(err, adventure){
 if (err) consoel.log(err);
 console.log(adventure);
});

//where
//查询数据类型是字符串时，可支持正则
animalMode.where('age', '2').exec(function(err, cat){
 if (err) console.log(err);
 console.log(cat);
});

animalMode
 .where('age').gte(1).lte(10)
 .where('name', 'catName')
 .exec(function(err, cat){
  if (err) console.log(err);
  console.log(cat);
 });

animalMode.update({name: 'catName'}, {age: '6'}, {multi : true}, function(err, numberAffected, raw){
 if (err) return console.log(err);
 console.log('The number of updated documents was %d', numberAffected);
 console.log('The raw response from Mongo was ', raw);
});

animalMode.remove({age: 6}, function(err){
 if (err) console.log(err);
})

animalMode.count({age: 2}, function(err, cat){
 if (err) console.log(err);
 console.log(cat);
})