首先，我编写了在数据库中保存fruit和person文档的代码。然后，我添加了最后几行代码来读取所有fruit文档。下面是我的JavaScript代码：

// getting-started.js
const mongoose = require('mongoose');

main().catch(err => console.log(err));

async function main() {
  await mongoose.connect('mongodb://localhost:27017/test');

  // use `await mongoose.connect('mongodb://user:password@localhost:27017/test');` if your database has auth enabled
}

//create a SCHEMA that sets out the fields each document will have and their datatypes
const fruitSchema = new mongoose.Schema({
  name: String
});

//create a MODEL
const Fruit = mongoose.model('Fruit', fruitSchema);

//create a DOCUMENT
const fruit = new Fruit({
  name: 'Apple',
  rating: 7,
  review: "Great!"
});

//save the document
fruit.save();
//(we comment it in case you do not want to save the same thing every time)

const personSchema = new mongoose.Schema(
  {
    name:String,
    age:Number,
  }
);

const Person = mongoose.model('Person', personSchema);

const person = new Person({
  name:"Alice",
  age:45
})

//person.save();

const kiwi = new Fruit({
   name: 'Kiwi',
   score: 10,
   review: 'The best fruit!'
 });

 const orange = new Fruit({
   name: 'Orange',
   score: 4,
   review: 'Too sour for me'
 });

 const banana = new Fruit({
   name: 'Banana',
   score: 3,
   review: 'Weird texture'
 });

 /*Fruit.insertMany([kiwi, orange, banana], function(err){
    if (err) {
      console.log(err);
    } else {
      console.log('Successfully saved all the fruits to FruitsDB');
    }
  });*/

  Fruit.find(function(err,fruits){
    if(err){
      console.log(err);
    }
    else{
      console.log(fruits);
    }
  })

这是我的跑步成绩：

$ node app.js
[
  {
    _id: new ObjectId("6349856a38dadec09142ade8"),
    name: 'Kiwi',
    __v: 0
  },
  {
    _id: new ObjectId("6349856a38dadec09142ade9"),
    name: 'Orange',
    __v: 0
  },
  {
    _id: new ObjectId("6349856a38dadec09142adea"),
    name: 'Banana',
    __v: 0
  },
  {
    _id: new ObjectId("63498906b285b3fc1887f99f"),
    name: 'Apple',
    __v: 0
  },
  {
    _id: new ObjectId("63498906b285b3fc1887f9a1"),
    name: 'Kiwi',
    __v: 0
  },
  {
    _id: new ObjectId("63498906b285b3fc1887f9a2"),
    name: 'Orange',
    __v: 0
  },
  {
    _id: new ObjectId("63498906b285b3fc1887f9a3"),
    name: 'Banana',
    __v: 0
  },
  {
    _id: new ObjectId("634a2e34d99e79b07647f88f"),
    name: 'Apple',
    __v: 0
  }
]

你可以看到结果中没有评论和评分。只有名字出现。我想知道为什么会是这样。