MongoDB聚合查询$ match不返回日期范围，为什么？

Question

I can't get the following MongoDB aggregation query to return a result. It only returns an empty array. I believe it's because it's not processing the date range correctly. However, when I do PriceHourly.find({ date: { $lt: end, $gt: start }}) the records are returned as expected...

    var start       = moment.utc('03-02-2012').startOf('day');
    var end         = moment.utc('03-02-2012').add('days',1).startOf('day');

    PriceHourly.aggregate([
        { $match: { date: { $gt: start, $lt: end } } },
        { $group: { _id: null, avgPrice: { $avg: '$price' } } }

    ], function(err, results){
        console.log(err, results);
    });

// Model
var PriceHourlySchema = new Schema({
    created: {
        type: Date,
        default: Date.now
    },
    full_date: {
        type: String,
        required: true,
        trim: true
    },
    day: {
        type: String,
        required: true,
        trim: true
    },
    hour: {
        type: String,
        required: true,
        trim: true
    },
    price: {
        type: Number,
        required: true
    },
    date: {
        type: Date,
        required: true
    }
}, 
{ 
    autoIndex: true 
});

Answer 1

MongoDB Aggregation Framework's $match did not understand the Moment Date objects I submitted. $match appears to only work with native Javascript date objects. So, if you'd still like to use Moment.js with $match, simply convert the Moment.js Date Objects to Native Javascript Date Objects using Moment's toDate() method, like this:

var start       = moment.utc(req.query.start).startOf('year').toDate();
var end         = moment.utc(req.query.start).add('years',1).startOf('year').add('hours',1).toDate();