Notes

#DB Migration

I learned how to download and setup MongoDB on my ubuntu system, for that I have to go to MongoDB documentation (https://www.mongodb.com/docs/manual/tutorial/install-mongodb-on-ubuntu), and follow th e process.

I have to isntall gnuppg and curl if they are not installed by using [sudo apt-get install gnupg curl], then import the mongodbpublic gpg key using [curl -fsSL https://www.mongodb.org/static/pgp/server-7.0.asc | sudo gpg -o /usr/share/keyrings/mongodb-server-7.0.gpg --dearmor], then create a list file for my version of ubuntu using [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], then run [sudo apt-get update], then run [sudo apt-get install -y mongodb-org], then start mongod service using [sudo systemctl start mongod], then I can check status by using [sudo systemctl status mongod], then I can connect to mongod using command [mongosh].

Then I can us command [use admin ] to switch to the admin user in mongodb and use [db.createUser({user:"admin", pwd:"password", roles:[{role:"root", db:"admin"}]})] to create credentials for user -> admin, and I can now exit mongosh and restart the mongod service by using [sudo systemctl restart mongod]

and then I can login to mongosh using this credetial by using the command [mongosh -u admin -p admin123 --authenticationDatabase admin]

I went to the link [https://www.mongodb.com/try/download/compass] and downloaded the mongodb compass pacakage and intalled it though apt package manager, This is a GUI to interact with mongodb and I can perform everthing though the GUI also.

I created on database and switched into it using the command [use smapledb] and then I ran this command [for (var i = 1; i <= 100000; i++) {
db.users.insertOne({
name: "User" + i,
age: Math.floor(Math.random() * 50) + 18,
email: "user" + i + "@example.com",
country: ["USA", "Canada", "UK", "Germany", "France"][Math.floor(Math.random() * 5)]
});
}]
It inserted 1 lakhs data into my database in users table.

I used command [mongoexport --db=sampledb --collection=users --type=csv --fields=_id,name,age,email,country,address --out=/home/princekumar/sample.csv], to export my data to csv file, here --db is for databasename, --collection is for tables and --fileds is for fields I want to export.