What are the 4 basic operations in MongoDB?

MongoDB, being a NoSQL database, revolves around collections and documents instead of tables and rows. Its four basic operations, also known as CRUD operations, are:

1. Create

This operation is used to add new documents to a collection. It corresponds to inserting data.

• Command: insertOne() or insertMany()
• Example:

  db.users.insertOne({ name: "Alice", age: 30 });
  db.users.insertMany([{ name: "Bob", age: 25 }, { name: "Charlie", age: 35 }]);

2. Read

This operation retrieves documents from a collection. You can use queries to filter and find specific data.

• Command: find() or findOne()
• Example:

  db.users.find({ age: { $gt: 25 } }); // Find users older than 25
  db.users.findOne({ name: "Alice" }); // Find the first user named Alice

3. Update

This operation modifies existing documents in a collection. You can update one or multiple documents.

• Command: updateOne(), updateMany(), or replaceOne()
• Example:

  db.users.updateOne({ name: "Alice" }, { $set: { age: 31 } }); // Update Alice's age to 31
  db.users.updateMany({}, { $inc: { age: 1 } }); // Increment age of all users by 1

4. Delete

This operation removes documents from a collection. You can delete one or multiple documents.

• Command: deleteOne() or deleteMany()
• Example:

  db.users.deleteOne({ name: "Alice" }); // Delete the first document named Alice
  db.users.deleteMany({ age: { $lt: 30 } }); // Delete all users younger than 30

Learn MongoDB Efficiently

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• Grokking SQL for Tech Interviews: Helps bridge SQL and MongoDB knowledge. Check it out here
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Understanding these operations is essential for mastering MongoDB's capabilities in application development and data management.