How to write the following mongo query in springboot?

[Vartika_Malguri]

query –

db.collection.find().sort({$natural: -1 }).limit(5)

I was basically finding the most recent documents in the collection. But how should I write this query in springboot?

[Aasawari (Aasawari Sahasrabuddhe)]

Hi @Vartika_Malguri
Welcome to the community forum!

MongoDB Compass provides the feature to convert the MongoDB query to a specific programming language. Please refer to the following documentation

Export Query to Specific Language — MongoDB Compass

However, this would be the Java code:

/*
 * Requires the MongoDB Java Driver.
 * https://mongodb.github.io/mongo-java-driver
 */

Bson filter = new Document();
Bson sort = new Document("$natural", -1L);

MongoClient mongoClient = new MongoClient(
    new MongoClientURI(
        "mongodb+srv://m001-student:m001-mongodb-basics@sandbox.6yvnh.mongodb.net/test?authSource=admin&replicaSet=atlas-gbccyn-shard-0&readPreference=primary&ssl=true"
    )
);
MongoDatabase database = mongoClient.getDatabase("sample_analytics");
MongoCollection<Document> collection = database.getCollection("accounts");
FindIterable<Document> result = collection.find(filter)
    .sort(sort)
    .limit((int)5L);

OR

    CriteriaDefinition filter = (CriteriaDefinition) new Document();
    List sort = (List) new Document("$natural", -1L);

    MongoClient mongoClient = new MongoClient(
    new MongoClientURI(
        "mongodb+srv://m001-student:m001-mongodb-basics@sandbox.6yvnh.mongodb.net/test?authSource=admin&replicaSet=atlas-gbccyn-shard-0&readPreference=primary&ssl=true"
    )
);
    Query query = new Query().addCriteria(filter).with(Sort.by(sort));

@Vartika_Malguri

basically finding the most recent documents in the collection

Please note that $natural is “The order in which the database refers to documents on disk” (see [$natural]( https://www.mongodb.com/docs/manual/reference/glossary/#std-term-natural-order` ) ), thus it may not sort based on the most recent inserted documents. Realistically, you may be able to drop the natural sort criteria and receive the same ordering of documents. If it is feasible for you to modify the schema design to have a createdAtfield, thecreatedAt` field could be used to sort the data as per the requirements.

Also, would recommend you to visit the following documentation

• Spring Boot Integration With MongoDB Tutorial | MongoDB for more understanding on integrating MongoDB with Spring boot application and explains how to access MongoDB data using the typical spring boot methods.

• https://www.mongodb.com/docs/manual/tutorial/query-documents/ you can refer to the mentioned document to read more on how to work with query by selecting the required language.

• Getting Started with MongoDB and Java - CRUD Operations Tutorial This blog post tutorial would help you to understand on how to perform CRUD operations with MongoDB using Java.

PS: I would also recommend you to go through the following course
MongoDB Courses and Trainings | MongoDB University to understand and learn more on MongoDB with Java.

Let us know if you have any more doubts.

Thanks
Aasawari