MongoDB：结合文本搜索和地理空间查询

我想知道是否有可能结合文本搜索和对结果运行地理空间查询/我将如何做。我现在正在使用Mongoose，但不介意直接使用Mongo来执行命令

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我试图做的是允许用户搜索产品并返回特定位置内的结果。我有两个单独运行的命令，但不知道如何组合它们。

您可以通过添加筛选参数筛选文本搜索（我正在使用）：

如果您想进行粗略的地理搜索，可以通过在经纬度周围定义最小值和最大值来过滤结果：

var distances = {'200m': 0.002, '500m': 0.005, '1km': 0.01, '5km': 0.05 }

  , distance = distances[reqDis];


var query = {
  latitude: { $lt: reqLat+distance, $gt: reqLat-distance },
  longitude: { $lt: reqLng+distance, $gt: reqLng-distance }
};

// put the query in the db.command as described above

---

mongodb文档中有一些关于这个主题的内容：

mongodb本身不支持同时进行文本和地理搜索。

但是您可以组合查询并获得结果

解决

+

+

+（或）

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这是一个非常常见的需求，在一个用例中需要地理过滤器和文本搜索，不幸的是mongodb还没有直接支持

下面的代码使用mongoose驱动程序，首先根据位置（经度和纬度）过滤文档，然后根据搜索词进一步过滤

var area = {
    center: [51, -114], //lng = 51 and lat = -114
    radius: 100,
    unique: true //this option is deprecated from MongoDB 2.6 on as mongodb no longer returns duplicate results
};

var query = Post.where('loc').within().circle(area) //Step 1: filter based on location
    //Step 2: Next filter on the basis of searched text
    .where({
        $text: {
            $search: < searchTerm >
        }
    }, {
        score: {
            $meta: 'textScore'
        }
    })
    //Step 3: Filter any document fields that should not be returned in the result
    .select({
        "val1": 0,
        "val2": 0
    });

//Execute the query
query.exec(function (err, result) {
    if (err) {
        //return error in the response
    }
    //return result object in the response
});

---

要使地理位置搜索和文本搜索都起作用，请确保在loc字段和文本字段上有索引。这里有更多细节。而且

使用地理空间数据库可以进行全文搜索

您可以在mongo shell中尝试以下操作：

db.collection.aggregate([
    { "$geoNear": {
        "near": {
            "type": "Point",
            "coordinates": [
               -73.86,
               41.076
            ]
        },
        "spherical": true,
        "maxDistance": 600,
        "distanceField": "distance",
        "query": {
           "fieldname": /querystring/
        }
    }}
])

使用全文搜索：

db.collection.find({
    "$text": { "$search": "query string" },
    "location": {    // this will your field name
        "$geoWithin": {
            "$centerSphere": [[
               -73.86,
               43.03
            ], 500 ]
        }
    }
}) 

---

如果纬度和经度存储在数组中，是否可以使用$lt和$gt运算符；类似于-loc[50.433234,20220123]

YourCollection.mapReduce(map, reduce, {out: {inline:1, query : yourFirstQuery}}, function(err, yourNewCollection) {
// Mapreduce returns the temporary collection with the results
    collection.find(yourNewQuery, function(err, result) {
      //your awsome code
    });
});

var area = {
    center: [51, -114], //lng = 51 and lat = -114
    radius: 100,
    unique: true //this option is deprecated from MongoDB 2.6 on as mongodb no longer returns duplicate results
};

var query = Post.where('loc').within().circle(area) //Step 1: filter based on location
    //Step 2: Next filter on the basis of searched text
    .where({
        $text: {
            $search: < searchTerm >
        }
    }, {
        score: {
            $meta: 'textScore'
        }
    })
    //Step 3: Filter any document fields that should not be returned in the result
    .select({
        "val1": 0,
        "val2": 0
    });

//Execute the query
query.exec(function (err, result) {
    if (err) {
        //return error in the response
    }
    //return result object in the response
});

var PostSchema = new Schema({
    title: String,
    description: String,
    loc: {
        type: [Number], // [<longitude>, <latitude>]
        index: '2d' // create the geospatial index
    }
    //some other fields
}

module.exports = mongoose.model('Post', PostSchema);

var lowerLeft = [40.73083, -73.99756]
var upperRight= [40.741404,  -73.988135]
query.where('loc').within().box(lowerLeft, upperRight)

db.collection.aggregate([
    { "$geoNear": {
        "near": {
            "type": "Point",
            "coordinates": [
               -73.86,
               41.076
            ]
        },
        "spherical": true,
        "maxDistance": 600,
        "distanceField": "distance",
        "query": {
           "fieldname": /querystring/
        }
    }}
])

db.collection.find({
    "$text": { "$search": "query string" },
    "location": {    // this will your field name
        "$geoWithin": {
            "$centerSphere": [[
               -73.86,
               43.03
            ], 500 ]
        }
    }
})