我正在使用node和mongodb编写应用程序，我无法进行任何地理位置查询。我通过发帖发送此查询：
{
"geometry": {
"type": "Point",
"coordinates" : [-8.139530, -79.032231 ]
}
}
这是我服务器的输出：
{ MongoError: Unable to execute query: error processing query: ns=dblocations.locations limit=1000 skip=0
Tree: GEONEAR field=geometry maxdist=0.00125569 isNearSphere=0
Sort: {}
Proj: {}
planner returned error: unable to find index for $geoNear query
at Function.MongoError.create (/Users/giuseppemarotta/Documents/Mockinghi/node_modules/mongodb-core/lib/error.js:31:11)
at queryCallback (/Users/giuseppemarotta/Documents/Mockinghi/node_modules/mongodb-core/lib/cursor.js:198:34)
at /Users/giuseppemarotta/Documents/Mockinghi/node_modules/mongodb-core/lib/connection/pool.js:436:18
at _combinedTickCallback (internal/process/next_tick.js:67:7)
at process._tickCallback (internal/process/next_tick.js:98:9)
name: 'MongoError',
message: 'Unable to execute query: error processing query: ns=dblocations.locations limit=1000 skip=0\nTree: GEONEAR field=geometry maxdist
=0.00125569 isNearSphere=0\nSort: {}\nProj: {}\n planner returned error: unable to find index for $geoNear query',
'$err': 'Unable to execute query: error processing query: ns=dblocations.locations limit=1000 skip=0\nTree: GEONEAR field=geometry maxdist=
0.00125569 isNearSphere=0\nSort: {}\nProj: {}\n planner returned error: unable to find index for $geoNear query',
code: 17007 }
我曾尝试使用本机mongoshell / mongoose查询，但我无法使其正常工作。
这是我的位置架构：
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var LocationSchema = new mongoose.Schema({
name: String,
geometry: {
coordinates: { type: [Number], required:true }
},
created_by : { type: String, required: true},
category: String,
description: String,
rating: Number,
created_at: Date,
updated_at: Date
});
// on every save, add the date
LocationSchema.pre('save', function(next) {
// get the current date
var currentDate = new Date();
rating = 0 ;
// change the updated_at field to current date
this.updated_at = currentDate;
// if created_at doesn't exist, add to that field
if (!this.created_at)
this.created_at = currentDate;
next();
});
LocationSchema.index({ geometry: '2dsphere' });
module.exports=mongoose.model('Location', LocationSchema);
这是我的server.js：
//lets require/import the mongodb native drivers.
var mongoose = require('mongoose');
//We need to work with "MongoClient" interface in order to connect to a mongodb server.
// Connection URL. This is where your mongodb server is running.
var url = 'mongodb://--------:-------@ds021895.mlab.com:21895/dblocations';
var Location = require('./models/location');
var User = require('./models/user');
//lets require/import the mongodb native drivers.
var mongodb = require('mongodb');
//We need to work with "MongoClient" interface in order to connect to a mongodb server.
var MongoClient = mongodb.MongoClient;
mongoose.connect(url);
// server.js
// BASE SETUP
// =============================================================================
// call the packages we need
var express = require('express'); // call express
var app = express(); // define our app using express
var bodyParser = require('body-parser');
router.route('/query')
// create a location (accessed at POST http://localhost:8080/mockinghi/register)
.post(function(req, res) {
var limit = req.query.limit || 10;
limit=10;
// get the max distance or set it to 8 kilometers
var maxDistance = req.query.distance || 8;
var minDistance = 0;
// we need to convert the distance to radians
// the raduis of Earth is approximately 6371 kilometers
maxDistance /= 6371;
// get coordinates [ <longitude> , <latitude> ]
var coords = [];
console.log(req);
coords = req.body.geometry.coordinates;
console.log("coords = "+coords);
console.log("MAxDistance = "+maxDistance);
/*
// Use connect method to connect to the Server
MongoClient.connect(url, function (err, db) {
if (err) {
console.log('Unable to connect to the mongoDB server. Error:', err);
} else {
//HURRAY!! We are connected. :)
console.log('Connection established to', url);
var locations_col = db.collection('locations');
// do some work here with the database.
locations_col.createIndex({ "geometry": "2d" });
locations_col.createIndex({ "geometry.coordinates": "2d" });
locations_col.ensureIndex({ "geometry" : "2dsphere" });
locations_col.ensureIndex({ "geometry.coordinates" : "2dsphere" });
locations_col.find(
{
geometry: {
$near :
{
$geometry: { type: "Point",
coordinates:[ coords[0],
coords[1] ] },
$maxDistance: maxDistance
},
}
}
).toArray(function (err, result) {
if (err) {
console.log(err);
} else if (result.length) {
console.log('Found:', result);
} else {
console.log('No document(s) found with defined "find" criteria!');
}
}
);
//Close connection
db.close();
}
});
*/
// find a location
Location.find({
loc: {
$near :
{
$geometry: { type: "2d",
coordinates:[ coords[0],
coords[1] ] },
$maxDistance: maxDistance
},
}
}).limit(limit).exec(function(err, locations) {
if (err) {
return res.json(500, err);
}
//console.log(locations);
res.json(200, locations);
});
});
答案 0 :(得分：2)
您需要为条目创建索引，例如错误明确指出$geoNear没有索引。
db.collection_name.createIndex({"geometry.coordinates": "2dsphere"}))
答案 1 :(得分：1)
它需要是一个geojson对象，类型是一个字符串，但默认为一个点。还有其他一些东西，比如polygon，line等，但你只是存储点。请记住，坐标是[经度，纬度]
geometry: {
type: {
type: String,
default: "Point"
},
coordinates: {
type: [Number]
},
index: '2dsphere'
}
你也可以把索引放在
LocationSchema.index({geometry: '2dsphere'});
答案 2 :(得分：0)
将您的模型更改为：
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var LocationSchema = new mongoose.Schema({
name: String,
geometry: {
coordinates: { type: [Number], required:true }
},
created_by : { type: String, required: true},
category: String,
description: String,
rating: Number,
created_at: Date,
updated_at: Date
});
// on every save, add the date
LocationSchema.pre('save', function(next) {
// get the current date
var currentDate = new Date();
rating = 0 ;
// change the updated_at field to current date
this.updated_at = currentDate;
// if created_at doesn't exist, add to that field
if (!this.created_at)
this.created_at = currentDate;
next();
});
LocationSchema.index({ geometry: '2dsphere' });
module.exports=mongoose.model('Location', LocationSchema);