Install MongoDB & MongoDB Compass | Setup Guide (Windows, Mac, Linux)

# CHAPTER 2

Installing MongoDB and MongoDB Compass #

1. Introduction #

2. Learning Objectives #

• Download and install the MongoDB Community Server.

• Download and install MongoDB Compass.

• Understand the default MongoDB port and connection string.

• Connect Compass to your local localhost server.

• Open the built-in Mongo Shell (mongosh).

3. Windows Setup #

1. 1. Download: Go to the official MongoDB Download Center (mongodb.com/try/download/community) and download the Windows .msi installer.

1. 2. Install: Run the installer and choose "Complete" setup.

1. 3. Service: When prompted, choose "Install MongoDB as a Service". This ensures the database starts automatically when you turn on your computer.

1. 4. Compass: The installer will usually ask if you want to install MongoDB Compass. Leave this checked.

1. 5. Finish: Complete the installation.

4. macOS Setup #

# Tap the official MongoDB Homebrew repository
brew tap mongodb/brew

# Install the MongoDB Community Server
brew install mongodb-community@7.0

# Start the MongoDB service to run in the background
brew services start mongodb-community@7.0

*Note: You will need to download MongoDB Compass separately from the official website.*

5. Linux Setup (Ubuntu/Debian) #

# Import the public key
curl -fsSL https://pgp.mongodb.com/server-7.0.asc | sudo gpg -o /usr/share/keyrings/mongodb-server-7.0.gpg --dearmor

# Create the list file
echo "deb [ arch=amd64,arm64 signed-by=/usr/share/keyrings/mongodb-server-7.0.gpg ] https://repo.mongodb.org/apt/ubuntu jammy/mongodb-org/7.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-7.0.list

# Install MongoDB
sudo apt-get update
sudo apt-get install -y mongodb-org

# Start the service
sudo systemctl start mongod
sudo systemctl enable mongod

6. The MongoDB Connection String #

• mongodb://: The protocol.

• localhost: Your local machine.

• 27017: The default port that MongoDB actively listens on.

7. Connecting with MongoDB Compass #

1. 1. Open the MongoDB Compass application.

1. 2. You will see a "New Connection" screen.

1. 3. In the URI text box, it will likely pre-fill mongodb://localhost:27017.

1. 4. Click the green Connect button.

1. 5. You are in! On the left sidebar, you will see default system databases like admin, config, and local. Do not delete these.

8. The MongoDB Shell (mongosh) #

Using the Shell:

1. 1. Open your terminal (or Command Prompt).

1. 2. Type mongosh and hit Enter.

1. 3. You are now connected to the database!

1. 4. Type show dbs to see a list of your databases.

1. 5. Type exit to leave the shell.

9. Common Mistakes #

• Server Not Running: The most common error beginners face in Compass is ECONNREFUSED. This means your MongoDB Server is turned off! You must ensure the Windows Service is running, or run brew services start mongodb-community on Mac.

• Port Conflicts: If another software is already using port 27017, MongoDB will fail to start.

10. Best Practices #

• Secure Your Local DB (Later): By default, local MongoDB installations do not have a username or password. This is fine for learning on your laptop, but you MUST set up Authentication before putting a database on the public internet (We cover this in Chapter 22).

11. Exercises #

1. 1. Open MongoDB Compass and successfully connect to mongodb://localhost:27017.

1. 2. Open your terminal, type mongosh, and execute the show dbs command.

12. MongoDB Challenges #

13. MCQ Quiz with Answers #

14. Interview Questions #

• Q: If a junior developer reports they are getting an ECONNREFUSED error when trying to connect to mongodb://localhost:27017, what is the most likely architectural cause, and how do they fix it?

• Q: Explain the difference between the MongoDB Server daemon (mongod) and the MongoDB Shell (mongosh).

15. FAQs #

16. Summary #

17. Next Chapter Recommendation #