MongoDB

Getting Started

Installing MongoDB

On Mac OS

brew tap mongodb/brew
brew install mongodb-community

On Ubuntu

# Install GPG as a pre-requisite step
sudo apt-get install gnupg

# Add MongoDB's public GPG key to the `apt` program
wget -qO - https://www.mongodb.org/static/pgp/server-4.2.asc | sudo apt-key add -

# Add the MongoDB repository to the `apt` program's 'sources.list.d' directory
print "deb [ arch=amd64,arm64 ] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.2 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-4.2.list

# Update `apt` to register these changes
sudo apt-get update

# Install the latest version
sudo apt-get install -y mongodb-org

Launching MongoDB
- On Ubuntu
```
sudo systemctl start mongod
```
Stopping MongoDB
- On Ubuntu
```
sudo systemctl stop mongod
```
Restarting MongoDB
- On Ubuntu
```
sudo systemctl restart mongod
```

Setting up MongoDB to run on startup

On macOS

brew services start mongodb/brew/mongodb-community

On Ubuntu
```
sudo systemctl enable mongod
```

The config file is located at /usr/local/etc/mongod.conf
The config file is located at /etc/mongodb.conf

Configuring MongoDB

MongoDB config files are written in YAML, an example mongodb.conf file is provided below

Connecting to a MongoDB Atlas Server

# Using a single URI
mongo mongodb+srv://tommy:fighton@cluster-name.mongodb.net/dbname

# Using a URI and two flags
# Short Form
mongo 'mongodb+srv://cluster-name.mongodb.net/dbname' -u 'tommy' -p 'fighton'
# Long Form
mongo 'mongodb+srv://cluster-name.mongodb.net/dbname' --username 'tommy' --password 'fighton'

The MongoDB Shell

Databases

Show the name of the current database
```
db
```
Switch to the database example
```
use example
```

List all available databases
```
show dbs
```

Basic Operations in the Shell

There are 4 basic operations

Create
Read
Update
Delete

Create

Use the insert function to add a document to a collection.

Documents can be represented in JavaScript Object Notation JSON and then inserted, which helps add simplicity.

Insert post object into the blog collection

post = {
  "title": "Hello World",
  "content": "That's all folks.",
  "date": new Date()
}
db.blog.insert(post)

Delete

Remove the document containing the username tommy from the users collection
```
db.users.remove({
  username: "tommy"
})
```