$geometry - Amazon DocumentDB
示例（MongoDB 外壳）代码示例

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$geometry

Amazon DocumentDB 中的$geometry运算符用于在地理空间查询中指定 GeoJSON 几何对象。此运算符可与其他地理空间查询运算符（如$geoWithin和）结合使用$geoIntersects，对您的数据执行空间查询。

在亚马逊 DocumentDB 中，$geometry运算符支持以下 GeoJSON 几何类型：

  • Point

  • LineString

  • Polygon

  • MultiPoint

  • MultiLineString

  • MultiPolygon

  • GeometryCollection

参数

  • type: geoJSON 几何对象的类型，例如PointPolygon、等

  • coordinates：表示几何形状的坐标数组。坐标数组的结构取决于几何类型。

示例（MongoDB 外壳）

以下示例演示如何使用$geometry运算符在 Amazon DocumentDB 中执行$geoIntersects查询。

创建示例文档

db.locations.insertMany([
  { 
    "_id": 1,
    "name": "Location 1",
    "location": { 
      "type": "Point",
      "coordinates": [-73.983253, 40.753941]
    }
  },
  { 
    "_id": 2,
    "name": "Location 2", 
    "location": {
      "type": "Polygon",
      "coordinates": [[
        [-73.998427, 40.730309],
        [-73.954348, 40.730309],
        [-73.954348, 40.780816],
        [-73.998427, 40.780816],
        [-73.998427, 40.730309]
      ]]
    }
  }
]);

查询示例

db.locations.find({
  "location": {
    "$geoIntersects": {
      "$geometry": {
        "type": "Polygon",
        "coordinates": [[
          [-73.998, 40.730],
          [-73.954, 40.730],
          [-73.954, 40.781],
          [-73.998, 40.781],
          [-73.998, 40.730]
        ]]
      }
    }
  }
})

输出

[
  {
    "_id": 2,
    "name": "Location 2",
    "location": {
      "type": "Polygon",
      "coordinates": [
        [
          [-73.998427, 40.730309],
          [-73.954348, 40.730309],
          [-73.954348, 40.780816],
          [-73.998427, 40.780816],
          [-73.998427, 40.730309]
        ]
      ]
    }
  }
]

代码示例

要查看使用该$geometry命令的代码示例，请选择要使用的语言的选项卡：

Node.js
const { MongoClient } = require('mongodb');

async function example() {
  const client = await MongoClient.connect('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false');
  const db = client.db('test');
  const collection = db.collection('locations');

  const query = {
    "location": {
      "$geoIntersects": {
        "$geometry": {
          "type": "Polygon",
          "coordinates": [[
            [-73.998, 40.730],
            [-73.954, 40.730],
            [-73.954, 40.781],
            [-73.998, 40.781],
            [-73.998, 40.730]
          ]]
        }
      }
    }
  };

  const result = await collection.find(query).toArray();
  console.log(result);

  await client.close();
}

example();
Python
from pymongo import MongoClient

def example():
    client = MongoClient('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false')
    db = client['test']
    collection = db['locations']

    query = {
        "location": {
            "$geoIntersects": {
                "$geometry": {
                    "type": "Polygon",
                    "coordinates": [[
                        [-73.998, 40.730],
                        [-73.954, 40.730],
                        [-73.954, 40.781],
                        [-73.998, 40.781],
                        [-73.998, 40.730]
                    ]]
                }
            }
        }
    }

    result = list(collection.find(query))
    print(result)

    client.close()

example()