从 MongoDB 中读取数据

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using MongoDB.Bson;
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using MongoDB.Driver;
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// Replace the uri string with your MongoDB deployment's connection string.
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var uri = "mongodb+srv://<user>:<password>@<cluster-url>?retryWrites=true&writeConcern=majority";
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var client = new MongoClient(uri);
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// database and collection code goes here
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// find code goes here
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// iterate code goes here
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package main
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import (
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	"context"
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	"go.mongodb.org/mongo-driver/mongo"
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	"go.mongodb.org/mongo-driver/mongo/options"
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)
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func main() {
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	uri := "mongodb+srv://<user>:<password>@<cluster-url>?retryWrites=true&writeConcern=majority"
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	client, err := mongo.Connect(context.TODO(), options.Client().ApplyURI(uri))
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	if err != nil {
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		panic(err)
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	}
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	defer func() {
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		if err = client.Disconnect(context.TODO()); err != nil {
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			panic(err)
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		}
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	}()
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	// database and colletion code goes here
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	// find code goes here
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	// iterate code goes here
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}

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import com.mongodb.client.*;
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import com.mongodb.client.model.Filters.*;
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import org.bson.Document;
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import org.bson.conversions.Bson;
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public class CrudRead {
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    public static void main(String[] args) {
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        String uri = "mongodb+srv://<user>:<password>@<cluster-url>?retryWrites=true&writeConcern=majority";
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        try (MongoClient mongoClient = MongoClients.create(uri)) {
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            // database and collection code goes here
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            // find code goes here
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            // iterate code goes here
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        }
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    }
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}

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const { MongoClient } = require("mongodb");
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// Replace the uri string with your MongoDB deployment's connection string.
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const uri =
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  "mongodb+srv://<user>:<password>@<cluster-url>?retryWrites=true&writeConcern=majority";
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const client = new MongoClient(uri);
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async function run() {
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  try {
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    await client.connect();
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    // database and collection code goes here
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    // find code goes here
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    // iterate code goes here
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  } finally {
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    // Ensures that the client will close when you finish/error
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    await client.close();
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  }
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}
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run().catch(console.dir);

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from pymongo import MongoClient
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# Replace the uri string with your MongoDB deployment's connection string.
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uri = "mongodb+srv://<user>:<password>@<cluster-url>?retryWrites=true&writeConcern=majority"
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client = MongoClient(uri)
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# database and collection code goes here
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# find code goes here
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# iterate code goes here
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# Close the connection to MongoDB when you're done.
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client.close()

// database and collection code goes here
var db = client.GetDatabase("sample_guides");
var coll = db.GetCollection<BsonDocument>("planets");

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// database and colletion code goes here
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db := client.Database("sample_guides")
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coll := db.Collection("planets")

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// database and collection code goes here
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MongoDatabase db = mongoClient.getDatabase("sample_guides");
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MongoCollection<Document> coll = db.getCollection("planets");

// database and collection code goes here
const db = client.db("sample_guides");
const coll = db.collection("planets");

# database and collection code goes here
db = client.sample_guides
coll = db.planets

// find code goes here
var cursor = coll.AsQueryable();

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// find code goes here
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cursor, err := coll.Find(context.TODO(), bson.D{})
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if err != nil {
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	panic(err)
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}

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// find code goes here
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MongoCursor<Document> cursor = coll.find().iterator();

// find code goes here
const cursor = coll.find();

# find code goes here
cursor = coll.find()

// iterate code goes here
foreach (var document in cursor.ToEnumerable())
{
    Console.WriteLine(document);
}

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// iterate code goes here
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for cursor.Next(context.TODO()) {
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	var result bson.M
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	if err := cursor.Decode(&result); err != nil {
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		panic(err)
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	}
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	fmt.Println(result)
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}
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if err := cursor.Err(); err != nil {
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	panic(err)
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}

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// iterate code goes here
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try {
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    while (cursor.hasNext()) {
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        System.out.println(cursor.next().toJson());
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    }
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} finally {
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    cursor.close();
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}

// iterate code goes here
await cursor.forEach(console.log);

# iterate code goes here
for doc in cursor:
    print(doc)