MongoDB Quick Guide Summary

MongoDB is a popular NoSQL database that stores data in flexible, JSON-like documents. This guide provides an overview of its key concepts, features, and basic operations.

Key Concepts

• NoSQL Database: Unlike traditional SQL databases, MongoDB is designed to handle unstructured data and allows for a more flexible schema.
• Documents: Data is stored in documents, which are similar to JSON objects. Each document can have different fields and structures.
• Collections: Documents are grouped into collections, which are akin to tables in SQL databases.
• Database: A MongoDB instance can contain multiple databases, each with its own collections.

Features

• Schema-less: MongoDB allows you to store documents without a pre-defined schema, making it easier to manage data changes.
• Scalability: It supports horizontal scaling, allowing you to add more servers to handle increased loads.
• Rich Queries: MongoDB supports powerful query capabilities, including filtering, sorting, and aggregation.
• Replication: It provides high availability through replica sets, which are groups of MongoDB servers that maintain the same data.

Basic Operations

1. Installation

• Download and install MongoDB from the official website.
• Start the MongoDB server using the command: mongod.

2. Creating a Database

• Use the command: use myDatabase to create or switch to a database named myDatabase.

3. Creating a Collection

• Use the command: db.createCollection('myCollection') to create a collection named myCollection.

4. Inserting Documents

Insert a document into a collection using:

db.myCollection.insertOne({ name: "Alice", age: 25 });

5. Querying Documents

Retrieve documents with:

db.myCollection.find({ name: "Alice" });

6. Updating Documents

Update a document using:

db.myCollection.updateOne({ name: "Alice" }, { $set: { age: 26 } });

7. Deleting Documents

Remove a document with:

db.myCollection.deleteOne({ name: "Alice" });

Conclusion

MongoDB is a flexible and powerful database solution ideal for applications that require a dynamic schema and scalability. Understanding its core concepts and basic operations is essential for beginners looking to work with this NoSQL database.