MongoDB essentials: Setup and basic operations

MongoDB is a popular NoSQL database management system that is often used in the servers of modern applications. This blogpost shows the essentials of working with MongoDB.

1. Setup MongoDB in Ubuntu
   
   sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 9DA31620334BD75D9DCB49F368818C72E52529D4
   echo "deb [ arch=amd64 ] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-4.0.list
   sudo apt-get update
   sudo apt-get install -y mongodb-org
2. Start/Stop MongoDB server
   
   //Start
   sudo service mongod start
   //Check status and get the PID
   service mongod status
   //Check if mongodb is running
   ps -aux | grep 16822
   //Check if mongodb server is listening at default port 27017
   netstat -tulnp | grep 2701
   //Stop
   sudo service mongod stop
   //Restart
   sudo service mongod restart
   
3. Essential operations
   
   //Start Mongo Shell
   mongo
   //List all databases
   show dbs
   // Switch current database to DB_NAME. The mongo shell variable db is set to the current database.
   use DB_NAME
   //Print a list of users for current database
   show users
   //Print a list of all roles, both user-defined and built-in, for the current database
   show roles
   //Create database
   use mynewdb
   db.users.insert({ id: 1 })
   //Drop database
   db.dropDatabase()
   //Create a new collection in the current database
   db.createCollection("NewCollectionName")
   //Print a list of all collections for current database
   show collections
   //Add new document to a collection
   db.COLLECTION_NAME.insert(document)
   //Query document
   db.COLLECTION_NAME.find(condition)
   example: db.users.find({"id": 1001})
   //Show all documents
   db.COLLECTION_NAME.find();
   //Update document
   db.users.update(CONDITION, UPDATED DATA, OPTIONS)
   //Delete document
   db.COLLECTION_NAME.remove(CONDITION)
   //More SQL liked MongoDB commands
   LINK