MongoDB查询返回空数组 [英] MongoDB Query Returns Empty Array

问题描述

正在运行一个基本的快速应用程序，该应用程序已连接到将近0.5 GB的MongoDB数据库...当我运行时:

Have a basic express app going that is connected to an almost .5 GB MongoDB Database...When I run:

router.get('/', function(req, res, next) {
    medical_data.find({'State':'CT'}, function(err, data) {
    console.log(data)
    res.render('index');
    });
});

我得到一个返回的空白数组:

I get a blank array returned:

[]
GET / 304 87.233 ms - -
GET /stylesheets/style.css 304 4.842 ms - -

这是我要查询的来自MongoLab的条目:

Here is the entry from MongoLab that I'm trying to query for:

{
    "_id": {
        "$oid": "5671dfafd7f6fdd02436682e"
    },
    "Street": "65 KANE ST",
    "City": "WEST HARTFORD",
    "State": "CT"
}

这是我的medical_data模型:

And here is my medical_data model:

var mongoose = require('mongoose');

var medical_data_schema = new mongoose.Schema({
  Street: String,
  City: String,
  State: String
});

var medical_data = mongoose.model('medical_data', medical_data_schema);
// Make this available to our other files
module.exports = medical_data;

为什么我要找回空白数组?如果我运行 findOne 而不是 find ，我会在控制台中获得 null

Why am I getting a blank array back? If I run findOne instead of find I get null in the console

我之前曾经运行过其他成功的全节点应用程序，但是没有一个拥有如此大的数据库，所以我认为这可能是超时问题?我不确定，任何帮助都会很棒.

I've run other succesfull node apps before but none with a database as big as this, so I think it might be a timeout issue? I'm not sure, any help would be amazing.

推荐答案

在现有数据库之上安装Mongoose模式可能很棘手.首先，猫鼬会通过使模型名称复数来确定集合名称；因此，在您的情况下，Mongoose将使用集合 medical_datas ，而我的猜测是它实际上称为 medical_data .

Fitting a Mongoose schema on top of an existing database can be tricky. For one, Mongoose will determine the collection name by pluralizing the model name; so in your case, Mongoose will use the collection medical_datas, and my guess is that it's actually called medical_data.

您可以使用 collection 来指定用于架构的集合名称.代码> 选项:

You can specify the collection name to use for a schema by using the collection option:

var medical_data_schema = new mongoose.Schema({
  Street : String,
  City   : String,
  State  : String
}, { collection : 'medical_data' });

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