mongoose操作笔记

一、mongoose文档地址：

　　https://cn.mongoosedoc.top/docs/api.html#update_update

　　https://www.cnblogs.com/web-fengmin/p/6435681.html

二、mongoose连接数据库

var mongoose = require('mongoose');
mongoose.connect('mongodb://localhost/studentmange', {
  autoIndex: false,
  useNewUrlParser: true
})
mongoose.set('useCreateIndex', true);

var db = mongoose.connection
db.once('open', function(callback) {
  console.log('数据库链接成功');
})

module.exports = db

三、定义schema和创建实例对象（可以用new或者create两种方法）

var mongoose = require('mongoose');

var courseSchema = new mongoose.Schema({
  "cid": Number,
  "name": String,
  "students": [Number]
})

courseSchema.index({"cid": 1})

courseSchema.statics.addStudent = function(courses, sid, callback) {
  console.log('插入课程开始', courses, sid)
  for(var i=0; i< courses.length; i++) {
    Course.update({"cid": courses[i]}, {$push: {"student": sid}}, function() {
      console.log('课程添加报名成功')
    })
  }
}

var Course = mongoose.model('Course', courseSchema)

var course1 = new Course({
  "cid": 1,
  "name": "地理",
  "students": []
})
course1.save()

Course.create({"cid": 2,
  "name": "数学",
  "students": []
})

module.exports = Course

四、结合node.js做CURD 和 DAO层的封装

exports.add = function(req, res, next) {
  Student.create(req.query, function() {
    console.log('插入学生成功')
    res.send('success')
    Course.addStudent(req.query.courses, req.query.sid, function() {
      console.log('插入课程成功');
    })
  })
}

exports.getAll = function(req, res, next) {
  Student.find({}, function(err, result) {
    res.send(result)
  })
}

exports.query = function(req, res, next) {
  Student.findOne({"sid": req.query.sid}, function(err, result) {
    console.log(result, 'query')
    res.send(result)
  })
}

exports.edit = function(req, res, next) {
  console.log('更新 id ', req.query.sid)
  Student.update({"sid": req.query.sid},{ $set: req.query}, function(err) {
    res.send('修改成功')
  })
}

exports.remove = function(req, res, next) {
  console.log('删除 id '+ req.query.sid)
  Student.remove({"sid": req.query.sid}, function(err) {
    res.send('删除成功')
  })
}

五、常用的操作运算符：

　　$set $lt $gt $push $pull

 ===end 替他具体的细节看文档吧===