如何在同一个语句中使用填充和聚合? [英] how to use populate and aggregate in same statement?

问题描述

这是我的约会集合:

{ _id: ObjectId("518ee0bc9be1909012000002"), date: ISODate("2013-05-13T22:00:00Z"), patient:ObjectId("518ee0bc9be1909012000002") }

{ _id: ObjectId("518ee0bc9be1909012000002"), date: ISODate("2013-05-13T22:00:00Z"), patient:ObjectId("518ee0bc9be1909012000002") }

{ _id: ObjectId("518ee0bc9be1909012000002"), date: ISODate("2013-05-13T22:00:00Z"), patient:ObjectId("518ee0bc9be1909012000002") }

我使用聚合得到以下结果

I used aggregate to get the following result

{date: ISODate("2013-05-13T22:00:00Z"),
patients:[ObjectId("518ee0bc9be1909012000002"),ObjectId("518ee0bc9be1909012000002"),ObjectId("518ee0bc9be1909012000002")] }

像这样:

Appointments.aggregate([
{$group: {_id: '$date', patients: {$push: '$patient'}}},
{$project: {date: '$_id', patients: 1, _id: 0}}
], ...)

如何填写患者文档我证实了这一点，但它不起作用... Appointments.find({}).populate("patient").aggregate....

How can I populate the patient document I trued this but it doesn't work ... Appointments.find({}).populate("patient").aggregate....

换句话说，我可以在同一个语句中使用填充和聚合

In other words, can i use populate and aggregate at the same statement

请帮忙

推荐答案

使用最新版本的 mongoose (mongoose >= 3.6)，您可以但它需要第二个查询，并且使用不同的填充.聚合后，执行以下操作:

With the latest version of mongoose (mongoose >= 3.6), you can but it requires a second query, and using populate differently. After your aggregation, do this:

Patients.populate(result, {path: "patient"}, callback);

在 Mongoose API 和 猫鼬文档.

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