Use mongoose-CRUD operations

refer to: https://www.udemy.com/course/the-web-developer-bootcamp

 帮助文档：  https://mongoosejs.com/docs/queries.html

• insert many

index.js

const mongoose = require('mongoose');
mongoose.connect('mongodb://localhost:27017/MovieDB', { useNewUrlParser: true, useUnifiedTopology: true })
    .then(() => {
        console.log("Connected")
    })
    .catch(err => {
        console.log("error!")
        console.log(err)
    })
// 如何缩进？选中代码块，右键，foramt selection.


//Schema,相当于创建一个指定数据类型的数据表
const movieSchema = new mongoose.Schema({
    title: String,
    year: Number,
    score: Number,
    rating: String
});

//model.用我们所设定的shema来实力化的东西
// An instance of a model is called a document.
//Models are responsible for creating and reading documents from the underlying MongoDB database.
const Movie = mongoose.model('Movie', movieSchema);   //Mongo will create a collection called movies by our input "Movie"

Movie.insertMany([
    { title: 'Amelie', year: 2001, score: 8.3, rating: 'R' },
    { title: 'Alien', year: 1979, score: 8.1, rating: 'R' },
    { title: 'The Iron Giant', year: 1999, score: 7.5, rating: 'PG' },
    { title: 'Stand By Me', year: 1986, score: 8.6, rating: 'R' },
    { title: 'Moonrise Kingdom', year: 2012, score: 7.3, rating: 'PG-13' }
])
    .then(data => {
        console.log("IT WORKED!")
        console.log(data);
    })

运行node->.load index.js

然后到mongo shell查看

• find

1. 查找所有的movies： find({ })

2. 查找指定movie:  Movie.find({条件})。

• find the first match: findOne

• findByID:

• Updating, updateOne to update the first matching ，直接使用updateOne/updateMany不会返回具体信息，findOneAndUpdate会返回具体信息

返回修改后的结果{new: true}, score 改成了7.8

• delete

remove不会立马返回我们删除的对象信息，如果使用findOneAndDelete的话会有返回结果。