MongoDB Shell (mongosh) basics

Introduction

The MongoDB Shell (mongosh) lets you talk to your database using simple commands. It helps you see, add, or change data easily.

You want to quickly check what data is in your database.

You need to add new information to your database by typing commands.

You want to update or fix some data without using a complex program.

You are learning how MongoDB works by trying commands step-by-step.

You want to delete old or wrong data from your database.

Syntax

MongoDB

mongosh

// Show databases
show dbs

// Switch to a database
use databaseName

// Show collections (tables)
show collections

// Find documents in a collection
db.collectionName.find()

// Insert a document
db.collectionName.insertOne({key: "value"})

mongosh is the command to start the MongoDB shell.

Commands like show dbs and use help you navigate databases.

Examples

Lists all databases on the server.

MongoDB

show dbs

Switches to the database named 'myDatabase'.

MongoDB

use myDatabase

Shows all collections (like tables) in the current database.

MongoDB

show collections

Displays all documents (records) in the 'users' collection.

MongoDB

db.users.find()

Sample Program

This example connects to MongoDB, switches to 'testDB', shows collections, adds a product, and then shows all products.

MongoDB

mongosh

show dbs
use testDB
show collections
db.products.insertOne({name: "Pen", price: 1.5})
db.products.find()

Important Notes

Commands are case-sensitive; type them exactly as shown.

Use db.collectionName.find().pretty() to see results in a readable format.

Remember to switch to the right database before running commands.

Summary

mongosh is your tool to interact with MongoDB using commands.

Use show dbs, use, and show collections to explore your data.

Insert and find data easily with insertOne() and find().