无法从 Mongodb 检索经度，长$near查询的记录

Question

我对mongodb的地理空间数据搜索非常陌生。我需要检索英国的邮政编码（结果纬度，基于长）接近我提供的纬度，长整型。我的 mongodb 查询如下：

$mongoPostcode = MongoDbConnector::getCollection("postcodes");
$query = array(
'location' => array(
    '$near' => array(
        'latitude' => 57.14270109,
        'longitude' => -2.093014619,
        '$maxDistance' => 15 / 111.12 // 1 degree is approximately 111.12 kilometers. 15 km of 111.12 would be 15/111.12
    )
)
);
$nearByPostcodeData = $mongoPostcode->find($query);

我的 mongo 的原始记录条目如下所示：

{
"_id": {
"$oid": "56ced2e6cffa1906847b6868"
},
"postcode": "AB11 8RQ",
"location": {
"latitude": 57.13597762,
"longitude": -2.072114784
},
"timestamp": 1454601532,
"active_status": 1
}

但是当我搜索时，它会返回以下错误：

Fatal error: Uncaught exception 'MongoCursorException' with message 'localhost:27017: Unable to execute query: error processing query: ns=sampleproject.postcodes limit=0 skip=0 Tree: GEONEAR field=location maxdist=0.134989 isNearSphere=1 Sort: {} Proj: {} planner returned error: unable to find index for $geoNear query' in C:xampphtdocssampleprojectfilesphpsearchByPostCode.php:35 Stack trace: #0 C:xampphtdocssampleprojectfilesphpsearchByPostCode.php(35): MongoCursor->rewind() #1 {main} thrown in C:xampphtdocssampleprojectfilesphpsearchByPostCode.php on line 35

示例数据建模中是否缺少任何内容，或者是否是查询问题？

Answer 1

您需要创建一个特殊的索引。 2D 球体索引

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

编辑

您可以修改集合以使用米而不是弧度进行查询。

{
    "_id": { "$oid": "56ced2e6cffa1906847b6868" },
    "postcode": "AB11 8RQ",
    "location": {
        "type": "Point",
        "coordinates": [
            -2.072114784, // Longitude
            57.13597762 // Latitude
        ]
     },
     "timestamp": 1454601532,
     "active_status": 1
 }

您的查询将如下所示：

$query = array(
    'location' => array(
        '$near' => array(
            'latitude' => 57.14270109,
            'longitude' => -2.093014619,
            '$maxDistance' => 1000 // 1000 meters        )
        )
     )
);

这需要重塑您的整个系列。详细信息可以在这里找到。