在mongoose中用$near查询获取数据位置时出错。

Question

query = {
  "location" : {
       "$near" : {
                    "$geometry": {
                        "type": "Point" ,
                        "coordinates": [18.55,73.78]
                    }
                }
            }
       }
  }






planner returned error: unable to find index for $geoNear query
    at Connection.<anonymous> (D:\Projects\api\node_modules\mongodb-core\lib\connection\pool.js:443:61)
    at Connection.emit (events.js:198:13)
    at Connection.EventEmitter.emit (domain.js:466:23)
    at processMessage (D:\Projects\api\node_modules\mongodb-core\lib\connection\connection.js:364:10)
    at Socket.<anonymous> (D:\Projects\api\node_modules\mongodb-core\lib\connection\connection.js:533:15)
    at Socket.emit (events.js:198:13)
    at Socket.EventEmitter.emit (domain.js:466:23)
    at addChunk (_stream_readable.js:288:12)
    at readableAddChunk (_stream_readable.js:269:11)
    at Socket.Readable.push (_stream_readable.js:224:10)
    at TCP.onStreamRead [as onread] (internal/stream_base_commons.js:94:17)
  ok: 0,

为此，我创建了 2dsphere 在以下链接中指定的位置字段上

https:/docs.mongodb.commanualcore2dsphere。

db.collectionName.createIndex( { location : "2dsphere" } )

帮助我了解我是否做错了什么。

Answer 1

尝试改变 $near 到 $nearSphere 并加 $minDistance: 0 和 $maxDistance: yourmaxdistance 旁边 $geometry 如果还是不行的话......那么它就会看起来像

query = {
  location: {
     $nearSphere: {
        $geometry: {
            type: "Point" ,
            coordinates: [18.55,73.78],
        },
        $minDistance: 0,
        $maxDistance: //your max will go here
     }
  }
}

如果上面的方法不奏效，请再次尝试创建索引，并留意输出结果......。

下面是一个创建索引失败的例子......

{
        "ok" : 0,
        "errmsg" : "Unknown index plugin '2dSphere'",
        "code" : 67,
        "codeName" : "CannotCreateIndex",
        "operationTime" : Timestamp(1590940517, 1),
        "$clusterTime" : {
                "clusterTime" : Timestamp(1590940517, 1),
                "signature" : {
                        "hash" : BinData(0,""),
                        "keyId" : NumberLong("")
                }
        }
}