MongoDB

Administer MongoDB NoSQL databases.

Installation & Setup

Install

apt install mongodb-org

Start service

systemctl start mongod

Connect

mongosh

Create user

use admin db.createUser({ user: "admin", pwd: "secret", roles: ["root"] })

Basic Operations

// Create database and collection use mydb db.users.insertOne({ name: "John", email: "john@example.com" })

// Query db.users.find({ name: "John" }) db.users.find().sort({ name: 1 }).limit(10)

// Index db.users.createIndex({ email: 1 }, { unique: true })

Replica Set

// Initialize replica set rs.initiate({ _id: "myReplicaSet", members: [ { _id: 0, host: "mongo1:27017" }, { _id: 1, host: "mongo2:27017" }, { _id: 2, host: "mongo3:27017" } ] })

Backup

Backup

mongodump --out /backup/

Restore

mongorestore /backup/

Best Practices

• Use replica sets in production

• Implement proper indexing

• Enable authentication

• Regular backups with mongodump