Basic MongoDB Note:

##Install MongoDB on Ubuntu

->Run the following command to import the MongoDB public GPG key −

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 7F0CEB10

->Create a /etc/apt/sources.list.d/mongodb.list file using the following command.

wget -qO - https://www.mongodb.org/static/pgp/server-4.4.asc | sudo apt-key add -

->However, if you receive an error indicating that gnupg is not installed, you can: --Install gnupg and its required libraries using the following command:

sudo apt-get install gnupg

->Once installed, retry importing the key:

`wget -qO - https://www.mongodb.org/static/pgp/server-4.4.asc | sudo apt-key add - `

->Create a list file for MongoDB

echo "deb [ arch=amd64,arm64 ] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.4 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-4.4.list

->Now issue the following command to update the repository:

sudo apt-get update

->Next install the MongoDB by using the following command :

sudo apt-get install -y mongodb-org

->If you are unsure which init system your platform uses, run the following command:

ps --no-headers -o comm 1

->Start MongoDB

sudo service mongodb start sudo systemctl start mongod sudo systemctl daemon-reload

->Stop MongoDB

sudo service mongodb stop

->Restart MongoDB

sudo service mongodb restart

->To use MongoDB run the following command. mongo

Common Command

show dbs # <=> Print a list of all databases on the server. use <db> # <=> Switch current database to <db> show collections # <=> Print a list of all collections for current database. db.people.insert({name:"Ashwin",gender:"m"}) # <=> Inserts a new "person" collection with a new object in that collection db.people.find(<any attributes or none>) # <=> Find all persons in the collection db.people.update({name:"Ashwin"},{gender:"f"}) # <=> Updates the selected (1st parameter) person with new value(2nd parameter) db.people.remove({name:"Ashwin"}) # <=> Remove where name is "Ashwin" db.people.drop() # <=> Delete the "people" collection