MongoDB 如何实现空间索引

如何在 MongoDB 中实现空间索引

javascript
// 连接到 MongoDB 数据库
const MongoClient = require('mongodb').MongoClient;
const uri = 'mongodb://localhost:27017';
const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });
// 创建地理空间索引
async function createSpatialIndex() {
  try {
    await client.connect();
    const db = client.db('mydb');
    const collection = db.collection('locations');
    await collection.createIndex({ location: '2dsphere' });
    console.log('地理空间索引创建成功！');
  } catch (err) {
    console.error('地理空间索引创建失败：', err);
  } finally {
    await client.close();
  }
}
createSpatialIndex();

javascript
// 连接到 MongoDB 数据库
const MongoClient = require('mongodb').MongoClient;
const uri = 'mongodb://localhost:27017';
const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });
// 查询附近的位置
async function findNearbyLocations() {
  try {
    await client.connect();
    const db = client.db('mydb');
    const collection = db.collection('locations');
    const nearbyLocations = await collection.find({
      location: {
        $near: {
          $geometry: {
            type: 'Point',
            coordinates: [longitude, latitude]
          },
          $maxDistance: 1000 // 距离范围（单位：米）
        }
      }
    }).toArray();
    console.log('附近的位置：', nearbyLocations);
  } catch (err) {
    console.error('查询附近的位置失败：', err);
  } finally {
    await client.close();
  }
}
findNearbyLocations();