Question

我正在尝试将$ near运算符与$ find（）一起使用，但是我无法完成它。我尝试了2种方法

userSchema

var userSchema = new db.Schema({
  email: { type: String, unique: true, lowercase: true },
  password: { type: String, select: false },
  company_name: String,
  location_verified: { type:Boolean, default:false},
  account_verified: { type:Boolean, default:false},
  date_joined: {type:Date, default:Date.now},
  business_details: {
    business_phone: String,
    business_email: String,
    business_location:[]
  }
})

//index as 2d 
userSchema.index({ 'business_detail.business_location': '2d' });
var User = db.model('User', userSchema);

方法1

    var limit = req.query.limit || 10;
    var maxDistance = req.query.distance || 8;
    maxDistance /= 6371;
    var coords = [];
    coords[0] = 101.6833;
    coords[1] = 3.1333;
    User.find({
      'business_details.business_location': {
        $near: coords,
        $maxDistance: maxDistance
      }
    }).limit(limit).exec(function(err, locations) {
      if (err) {
        console.log("The ERROR:"+err);
      }
      console.log("The RESULT:"+locations);
    });

方法2

    var limit = req.query.limit || 10;
    var maxDistance = req.query.distance || 8;
    maxDistance /= 6371;
    var coords = [];
    coords[0] = 101.6833;
    coords[1] = 3.1333;

User.find({
  'business_details': {
    $near:{
      $geometry:{'business_location':coords},
      $maxDistance: maxDistance
    }
  }
}).limit(limit).exec(function(err, locations) {
  if (err) {
    console.log("The ERROR:"+err);
  }
  console.log("The RESULT:"+locations);
});

我已经检查了我的数据库索引，我试图使用$ near的字段有2d索引

> db.system.indexes.find();
{ "v" : 1, "key" : { "_id" : 1 }, "name" : "_id_", "ns" : "clairvy.users" }
{ "v" : 1, "unique" : true, "key" : { "email" : 1 }, "name" : "email_1", "ns" : "clairvy.users", "background" : true, "safe" : null }
{ "v" : 1, "key" : { "business_detail.business_location" : "2d" }, "name" : "business_detail.business_location_2d", "ns" : "clairvy.users", "background" : true, "safe" : null }

这就是我的文档的样子

"_id" : ObjectId("557ae162d3fb543275135f04"),
    "company_name" : "john inc",
    "email" : "example@gmail.com",
    "password" : "$2a$10$SDAXG8TrqjJIbvyGjpyQQuJDMTTDjMlNdpNQ9brsf4otGKr/CqI5i",
    "business_details" : {
        "business_phone" : "011112",
        "business_email" : "example@gmail.com",
        "business_fb" : "https://www.youtube.com/watch?v=NA4otP-v6iI",
        "business_about_us" : " asd sad sad sadasd",
        "business_tags" : [
            {
                "name" : "Marina Augustine",
                "email" : "m.augustine@exampleas.com",
                "image" : "http://lorempixel.com/50/50/people?0",
                "_lowername" : "marina augustine"
            },
            {
                "name" : "Oddr Sarno",
                "email" : "o.sarno@exampleas.com",
                "image" : "http://lorempixel.com/50/50/people?1",
                "_lowername" : "oddr sarno"
            }
        ],
        "business_location" : [
            101.6867332275391,
            3.1285006558498596
        ],
        "business_price_range" : 2,
        "business_preparation_time_range" : 2
    }

这两种方法都给了我相同的结果，这就是错误"MongoError: n/a"我可能知道哪个部分犯了错误？感谢您的帮助，谢谢

Answer 1

您的索引位于错误的命名空间中。你有什么：

{ "business_detail.business_location" : "2d" },

应该是什么：

{ "business_details.business_location" : "2d" },

因此，此处的正确字段为＆＃34; business_detail s ＆＃34;，更正为：

db.users.ensureIndex({ "business_details.business_location": "2d })

或者在你的猫鼬模式中定义该索引。但是也要删除集合上任何其他错误命名的索引，因为某些＆＃34; geo＆＃34;命令被多个索引搞糊涂了。

db.users.dropIndex({ "business_detail.business_location": "2d" })

因为MongoDB是＆＃34;无模式的＆＃34;添加文档中不存在的索引不会产生任何错误。作为＆＃34;无模式＆＃34; MongoDB本身没有办法知道＆＃34;某天＆＃34;或者在某些文件＆＃34;这些数据可能存在。

添加到您的架构定义是一种很好的做法，因此您的代码中有一些内容可以反映您的意图：

userSchema.index({ "business_details.business_location": "2d" });

尝试使用find（）中的$ near进行查询时出错

1 个答案: