如何计算特定领域的情况下，在收集的mongodb

这是代收货款在我的mongodb。

{
studentIDnumber: "111"
datepicker: "02/06/2019"
transactType: "Graduation expenses"
timepicker:"11:00am - 12:00pm"
amount:"123"
}

{
studentIDnumber: "111"
datepicker: "02/03/2019"
transactType: "Diploma"
timepicker:"11:00am - 12:00pm"
amount:"123"
}

{
studentIDnumber: "111"
datepicker: "02/03/2019"
transactType: "Tuition fee"
timepicker:"11:00am - 12:00pm"
amount:"123"
}

我想算11:00多少 - 下午12:00集合中，但它给了我一个qazxsw POI，下面是我的代码的NodeJS。什么是这样做的正确方法？有任何想法吗？

UnhandledPromiseRejectionWarning: TypeError: Cannot read property 'count' of undefined

使用此查询：

const mongoose = require('mongoose')
const url = require('../config/keys').MongoURI

router.get('/dashboard', ensureAuthenticated, (req, res) =>{
  res.render('dashboard', {
    firstname: req.user.firstname,
    lastname : req.user.lastname
  }),

  mongoose.connect(url, {useNewUrlParser: true}, function(err, db){
    if (err) throw err
    db.payments.count({timepicker: "11:00am - 12:00pm"})

  })

});

如果您使用的是猫鼬，然后

db.payments.find({timepicker: "11:00am - 12:00pm"}).count(function(err, count) 
    {
        if (err) throw err;
        console.log(count);

    });

如何计算特定领域的情况下，在收集的mongodb

这是代收货款在我的mongodb。

{
studentIDnumber: "111"
datepicker: "02/06/2019"
transactType: "Graduation expenses"
timepicker:"11:00am - 12:00pm"
amount:"123"
}

{
studentIDnumber: "111"
datepicker: "02/03/2019"
transactType: "Diploma"
timepicker:"11:00am - 12:00pm"
amount:"123"
}

{
studentIDnumber: "111"
datepicker: "02/03/2019"
transactType: "Tuition fee"
timepicker:"11:00am - 12:00pm"
amount:"123"
}

我想算11:00多少 - 下午12:00集合中，但它给了我一个qazxsw POI，下面是我的代码的NodeJS。什么是这样做的正确方法？有任何想法吗？

UnhandledPromiseRejectionWarning: TypeError: Cannot read property 'count' of undefined

使用此查询：

const mongoose = require('mongoose')
const url = require('../config/keys').MongoURI

router.get('/dashboard', ensureAuthenticated, (req, res) =>{
  res.render('dashboard', {
    firstname: req.user.firstname,
    lastname : req.user.lastname
  }),

  mongoose.connect(url, {useNewUrlParser: true}, function(err, db){
    if (err) throw err
    db.payments.count({timepicker: "11:00am - 12:00pm"})

  })

});

如果您使用的是猫鼬，然后

db.payments.find({timepicker: "11:00am - 12:00pm"}).count(function(err, count) 
    {
        if (err) throw err;
        console.log(count);

    });