JavaScript kullanarak MongoDB için Azure Cosmos DB'de verileri sorgulama

ŞUNLAR IÇIN GEÇERLIDIR: MongoDB

Koleksiyondaki belgeleri bulmak ve işlemek için sorguları ve toplama işlem hatlarını kullanın.

Not

Örnek kod parçacıkları GitHub'da JavaScript projesi olarak kullanılabilir.

MongoDB için API başvuru belgeleri | MongoDB Paketi (npm)

Belgeler için sorgu

Belgeleri bulmak için bir sorgu kullanarak belgelerin nasıl bulunduğunu tanımlayın.

// assume doc exists

const product = {
  _id: new ObjectId('62b1f43a9446918500c875c5'),
  category: 'gear-surf-surfboards',
  name: 'Yamba Surfboard 7',
  quantity: 12,
  sale: false,
};

// For unsharded database: use id
const query1 = { _id: new ObjectId(product._id) };
const foundById = await client
  .db('adventureworks')
  .collection('products')
  .findOne(query1);
console.log(
  `Read doc:\t\n${Object.keys(foundById).map(key => `\t${key}: ${foundById[key]}\n`)}`
);

// For sharded database: point read doc from collection using the id and partitionKey
const query2 = { _id: new ObjectId(product._id), category: product.category };
const foundByIdAndPartitionKey = await client
  .db('adventureworks')
  .collection('products')
  .findOne(query2);
console.log(
  `Read doc 2:\t\n${Object.keys(foundByIdAndPartitionKey).map(key => `\t${key}: ${foundByIdAndPartitionKey[key]}\n`)}`
);

// Find one by unique doc property value
const query3 = { name: product.name };
const foundByUniqueValue = await client
  .db('adventureworks')
  .collection('products')
  .findOne(query3);
console.log(
  `Read doc 3:\t\n${Object.keys(foundByUniqueValue).map(key => `\t${key}: ${foundByUniqueValue[key]}\n`)}`
);

// Find one (with many that match query) still returns one doc
const query4 = { category: product.category };
const foundByNonUniqueValue = await client
  .db('adventureworks')
  .collection('products')
  .findOne(query4);
console.log(
  `Read doc 4:\t\n${Object.keys(foundByNonUniqueValue).map(key => `\t${key}: ${foundByNonUniqueValue[key]}\n`)}`
);

// Find all that match query
const query5 = { category: product.category };
const foundAll = await client
  .db('adventureworks')
  .collection('products')
  .find(query5)
  .sort({ _id: 1 })
  .toArray();
console.log(
  `Matching all in product category:\n${foundAll.map(doc => `\t${doc._id}: ${doc.name}\n`)}`
);

// Find all in collection with empty query {}
const foundAll2 = await client
  .db('adventureworks')
  .collection('products')
  .find({})
  .toArray();
console.log(
  `All docs:\n${foundAll2.map(doc => `\t${doc._id}: ${doc.name}\n`)}`
);

// Pagination - next 5 docs
// sort by name require an index on name
const nextFiveDocs = await client
  .db('adventureworks')
  .collection('products')
  .find({})
  .sort({ name: 1 })
  .skip(5)
  .limit(5)
  .toArray();
console.log(
  `Next 5 docs:\n${nextFiveDocs.map(doc => `\t${doc._id}: ${doc.name}\n`)}`
);

Yukarıdaki kod parçacığı aşağıdaki örnek konsol çıkışını görüntüler:

Read doc:
        _id: 62b1f43a9446918500c875c5
,       name: Yamba Surfboard-13
,       category: gear-surf-surfboards
,       quantity: 20
,       sale: false
,       discontinued: true

Read doc 2:
        _id: 62b1f43a9446918500c875c5
,       name: Yamba Surfboard-13
,       category: gear-surf-surfboards
,       quantity: 20
,       sale: false
,       discontinued: true

Read doc 3:
        _id: 62b23a371a09ed6441e5ee31
,       category: gear-surf-surfboards
,       name: Yamba Surfboard 7
,       quantity: 5
,       sale: true
,       discontinued: true

Read doc 4:
        _id: 62b1f43a9446918500c875c5
,       name: Yamba Surfboard-13
,       category: gear-surf-surfboards
,       quantity: 20
,       sale: false
,       discontinued: true

Matching all in product category:
        62b1f43a9446918500c875c5: Yamba Surfboard-13
,       62b1f4670c7af8c2942b7c10: Yamba Surfboard-3
,       62b1f46fa6546d2afb5715ac: Yamba Surfboard-90
,       62b1f474e4b43498c05d295b: Yamba Surfboard-9

All docs:
        62b1f43a9446918500c875c5: Yamba Surfboard-13
,       62b1f4670c7af8c2942b7c10: Yamba Surfboard-3
,       62b1f46fa6546d2afb5715ac: Yamba Surfboard-90
,       62b1f474e4b43498c05d295b: Yamba Surfboard-9
,       62b1f47896aa8cfa280edf2d: Yamba Surfboard-55
,       62b1f47dacbf04e86c8abf25: Yamba Surfboard-11
,       62b1f4804ee53f4c5c44778c: Yamba Surfboard-97
,       62b1f492ff69395b30a03169: Yamba Surfboard-93
,       62b23a371a09ed6441e5ee30: Yamba Surfboard 3
,       62b23a371a09ed6441e5ee31: Yamba Surfboard 7

All docs:
        62b1f43a9446918500c875c5: Yamba Surfboard-13
,       62b1f4670c7af8c2942b7c10: Yamba Surfboard-3
,       62b1f46fa6546d2afb5715ac: Yamba Surfboard-90
,       62b1f474e4b43498c05d295b: Yamba Surfboard-9
,       62b1f47896aa8cfa280edf2d: Yamba Surfboard-55
,       62b1f47dacbf04e86c8abf25: Yamba Surfboard-11
,       62b1f4804ee53f4c5c44778c: Yamba Surfboard-97
,       62b1f492ff69395b30a03169: Yamba Surfboard-93
,       62b23a371a09ed6441e5ee30: Yamba Surfboard 3
,       62b23a371a09ed6441e5ee31: Yamba Surfboard 7

done

Toplama işlem hatları

Toplama işlem hatları, bu işlemleri istemcide gerçekleştirmek yerine Azure Cosmos DB sunucunuzdaki pahalı sorgu hesaplamalarını, dönüştürmeleri ve diğer işlemleri yalıtmak için kullanışlıdır.

Belirli toplama işlem hattı desteği için aşağıdakilere bakın:

Toplama işlem hattı söz dizimi

İşlem hattı, JSON nesneleri olarak bir dizi aşamaya sahip bir dizidir.

const pipeline = [
    stage1,
    stage2
]

İşlem hattı aşaması söz dizimi

Aşama, işlemi ve uygulandığı verileri tanımlar, örneğin:

$match - belgeleri bulma
$addFields - genellikle önceki aşamadan imleçlere alan ekleme
$limit - imleçte döndürülen sonuç sayısını sınırlayın
$project - yeni veya mevcut alanları geçirin, hesaplanan alanlar olabilir
$group - sonuçları işlem hattındaki alana veya alanlara göre gruplandırma
$sort - sonuçları sıralama

// reduce collection to relative documents
const matchStage = {
    '$match': {
        'categoryName': { $regex: 'Bikes' },
    }
}

// sort documents on field `name`
const sortStage = { 
    '$sort': { 
        "name": 1 
    } 
},

Yinelenebilir imleç elde etmek için işlem hattını toplama

İşlem hattı, yinelenebilir bir imleç oluşturmak için toplanır.

const db = 'adventureworks';
const collection = 'products';

const aggCursor = client.db(databaseName).collection(collectionName).aggregate(pipeline);

await aggCursor.forEach(product => {
    console.log(JSON.stringify(product));
});

JavaScript'te toplama işlem hattı kullanma

İstemciye dönmeden önce sunucuda veri işlemeyi sürdürmek için bir işlem hattı kullanın.

Örnek ürün verileri

Aşağıdaki toplamalar, örnek ürün koleksiyonunu şu şekilde verilerle birlikte kullanır:

[
    {
        "_id": "08225A9E-F2B3-4FA3-AB08-8C70ADD6C3C2",
        "categoryId": "75BF1ACB-168D-469C-9AA3-1FD26BB4EA4C",
        "categoryName": "Bikes, Touring Bikes",
        "sku": "BK-T79U-50",
        "name": "Touring-1000 Blue, 50",
        "description": "The product called \"Touring-1000 Blue, 50\"",
        "price": 2384.0700000000002,
        "tags": [
        ]
    },
    {
        "_id": "0F124781-C991-48A9-ACF2-249771D44029",
        "categoryId": "56400CF3-446D-4C3F-B9B2-68286DA3BB99",
        "categoryName": "Bikes, Mountain Bikes",
        "sku": "BK-M68B-42",
        "name": "Mountain-200 Black, 42",
        "description": "The product called \"Mountain-200 Black, 42\"",
        "price": 2294.9899999999998,
        "tags": [
        ]
    },
    {
        "_id": "3FE1A99E-DE14-4D11-B635-F5D39258A0B9",
        "categoryId": "26C74104-40BC-4541-8EF5-9892F7F03D72",
        "categoryName": "Components, Saddles",
        "sku": "SE-T924",
        "name": "HL Touring Seat/Saddle",
        "description": "The product called \"HL Touring Seat/Saddle\"",
        "price": 52.640000000000001,
        "tags": [
        ]
    },
]

Örnek 1: Ürün alt kategorileri, ürün sayısı ve ortalama fiyat

Her bir ürün alt kategorisindeki ortalama fiyatı raporlamak için aşağıdaki örnek kodu kullanın.

// Goal: Find the average price of each product subcategory with
// the number of products in that subcategory.
// Sort by average price descending.

// Read .env file and set environment variables
import 'dotenv/config';

// Use official mongodb driver to connect to the server
import { MongoClient } from 'mongodb';

// New instance of MongoClient with connection string
// for Cosmos DB
const url = process.env.COSMOS_CONNECTION_STRING;
const client = new MongoClient(url);

export async function main() {
  try {
    // Use connect method to connect to the server
    await client.connect();

    // Group all products by category
    // Find average price of each category
    // Count # of products in each category
    const groupByCategory = {
      $group: {
        _id: '$categoryName',
        averagePrice: {
          $avg: '$price',
        },
        countOfProducts: {
          $sum: 1,
        },
      },
    };

    // Round price to 2 decimal places
    // Don't return _id
    // Rename category name help in `_id` to `categoryName`
    // Round prices to 2 decimal places
    // Rename property for countOfProducts to nProducts
    const additionalTransformations = {
      $project: {
        _id: 0,
        category: '$_id',
        nProducts: '$countOfProducts',
        averagePrice: { $round: ['$averagePrice', 2] },
      },
    };

    // Sort by average price descending
    const sort = { $sort: { $averagePrice: -1 } };

    // stages execute in order from top to bottom
    const pipeline = [groupByCategory, additionalTransformations, sort];

    const db = 'adventureworks';
    const collection = 'products';

    // Get iterable cursor
    const aggCursor = client.db(db).collection(collection).aggregate(pipeline);

    // Display each item in cursor
    await aggCursor.forEach(product => {
      console.log(JSON.stringify(product));
    });

    return 'done';
  } catch (err) {
    console.log(JSON.stringify(err));
  }
}

main()
  .then(console.log)
  .catch(console.error)
  .finally(() => {
    // Close the db and its underlying connections
    client.close();
  });

// Results:
// {"averagePrice":51.99,"category":"Clothing, Jerseys","nProducts":8}
// {"averagePrice":1683.36,"category":"Bikes, Mountain Bikes","nProducts":32}
// {"averagePrice":1597.45,"category":"Bikes, Road Bikes","nProducts":43}
// {"averagePrice":20.24,"category":"Components, Chains","nProducts":1}
// {"averagePrice":25,"category":"Accessories, Locks","nProducts":1}
// {"averagePrice":631.42,"category":"Components, Touring Frames","nProducts":18}
// {"averagePrice":9.25,"category":"Clothing, Socks","nProducts":4}
// {"averagePrice":125,"category":"Accessories, Panniers","nProducts":1}
// ... remaining fields ...

Örnek 2: Fiyat aralığına sahip bisiklet türleri

Alt kategoriyi raporlamak için aşağıdaki Bikes kullanın.

// Goal: Find the price range for the different bike subcategories.

import dotenv from 'dotenv';
import path from 'path';
const __dirname = path.resolve();

dotenv.config({ path: path.resolve(__dirname, '../.env') });

// Use official mongodb driver to connect to the server
import { MongoClient } from 'mongodb';

// New instance of MongoClient with connection string
// for Cosmos DB
const url = process.env.COSMOS_CONNECTION_STRING;
const client = new MongoClient(url);

export async function main() {
  try {
    // Use connect method to connect to the server
    await client.connect();

    const categoryName = 'Bikes';

    const findAllBikes = {
      $match: {
        categoryName: { $regex: categoryName },
      },
    };

    // Convert 'Bikes, Touring Bikes' to ['Bikes', 'Touring Bikes']
    const splitStringIntoCsvArray = {
      $addFields: {
        categories: { $split: ['$categoryName', ', '] },
      },
    };

    // Remove first element from array
    // Converts ['Bikes', 'Touring Bikes'] to ['Touring Bikes']
    const removeFirstElement = {
      $addFields: {
        subcategory: {
          $slice: [
            '$categories',
            1,
            { $subtract: [{ $size: '$categories' }, 1] },
          ],
        },
      },
    };

    // Group items by book subcategory, and find min, avg, and max price
    const groupBySubcategory = {
      $group: {
        _id: '$subcategory',
        maxPrice: {
          $max: '$price',
        },
        averagePrice: {
          $avg: '$price',
        },
        minPrice: {
          $min: '$price',
        },
        countOfProducts: {
          $sum: 1,
        },
      },
    };

    // Miscellaneous transformations
    // Don't return _id
    // Convert subcategory from array of 1 item to string in `name`
    // Round prices to 2 decimal places
    // Rename property for countOfProducts to nProducts
    const additionalTransformations = {
      $project: {
        _id: 0,
        name: { $arrayElemAt: ['$_id', 0] },
        nProducts: '$countOfProducts',
        min: { $round: ['$minPrice', 2] },
        avg: { $round: ['$averagePrice', 2] },
        max: { $round: ['$maxPrice', 2] },
      },
    };

    // Sort by subcategory
    const sortBySubcategory = { $sort: { name: 1 } };

    // stages execute in order from top to bottom
    const pipeline = [
      findAllBikes,
      splitStringIntoCsvArray,
      removeFirstElement,
      groupBySubcategory,
      additionalTransformations,
      sortBySubcategory,
    ];

    const db = 'adventureworks';
    const collection = 'products';

    // Get iterable cursor
    const aggCursor = client.db(db).collection(collection).aggregate(pipeline);

    // Display each item in cursor
    await aggCursor.forEach(product => {
      console.log(JSON.stringify(product));
    });

    return 'done';
  } catch (err) {
    console.log(JSON.stringify(err));
  }
}

main()
  .then(console.log)
  .catch(console.error)
  .finally(() => {
    // Close the db and its underlying connections
    client.close();
  });

// Results:
// {'name':'Mountain Bikes','nProducts':32,'min':539.99,'avg':1683.37,'max':3399.99}
// {'name':'Road Bikes','nProducts':43,'min':539.99,'avg':1597.45,'max':3578.27}
// {'name':'Touring Bikes','nProducts':22,'min':742.35,'avg':1425.25,'max':2384.07}

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Last updated on 2025-06-16