What is MongoDB & How to Install and use it

 MongoDB is a NoSQL database that stores data in a flexible, JSON-like format called BSON (Binary JSON).

 Unlike traditional relational databases like MySQL or PostgreSQL, which use tables and rows, 

MongoDB uses collections and documents.

Key Concepts

Concept	Description
Database	A container for collections.
Collection	A group of documents, similar to a table in SQL.
Document	A single record in a collection, stored as a JSON-like object.

 

Example of a document:

{
  "name": "Alice",
  "age": 30,
  "email": "alice@example.com"
}





Download it from :-


https://www.mongodb.com/try/download/community



for windows :-



and after installation open it :-


and create connection and connect it for example enter connection name as omsir :-




and then connect  it :-





and then you will see following here just click on local you will see open mongodb shell options:-


and then you will see Open MongoDb shell and click on it and apply queries :-





and then use queries in it to show collections as shown below :-




and now check data of records collection use following queries :-





📁 1. Insert Data into records Collection
db.records.insertMany([
  { name: "Alice", age: 30, city: "New York", status: "active" },
  { name: "Bob", age: 25, city: "Los Angeles", status: "inactive" },
  { name: "Charlie", age: 35, city: "Chicago", status: "active" },
  { name: "David", age: 28, city: "New York", status: "pending" },
  { name: "Eva", age: 40, city: "Los Angeles", status: "active" }
])


✏️ 2. Update a Document
🔹 Update one document (e.g., change Bob’s status to "active"):

db.records.updateOne(
  { name: "Bob" },
  { $set: { status: "active" } }
)



3. Filter / Search the Collection
🔸 Find all documents:

db.records.find()

🔸 Find by city:

db.records.find({ city: "New York" })

🔸 Find by status:

db.records.find({ status: "active" })

🔸 Find age greater than 30:

db.records.find({ age: { $gt: 30 } })

🔸 Find name starting with "A" (regex):

db.records.find({ name: /^A/ })

🔸 Combine filters (e.g., active users in LA):

db.records.find({
  city: "Los Angeles",
  status: "active"
})


 4. (Optional) Delete Documents
Delete one:

db.records.deleteOne({ name: "David" })

Delete all inactive users:

db.records.deleteMany({ status: "inactive" })




✅ Summary of All Commands (In Order)

use mydb

db.records.insertMany([
  { name: "Alice", age: 30, city: "New York", status: "active" },
  { name: "Bob", age: 25, city: "Los Angeles", status: "inactive" },
  { name: "Charlie", age: 35, city: "Chicago", status: "active" },
  { name: "David", age: 28, city: "New York", status: "pending" },
  { name: "Eva", age: 40, city: "Los Angeles", status: "active" }
])

db.records.updateOne(
  { name: "Bob" },
  { $set: { status: "active" } }
)

db.records.updateMany(
  { status: "pending" },
  { $set: { status: "inactive" } }
)

db.records.find()
db.records.find({ city: "New York" })
db.records.find({ status: "active" })
db.records.find({ age: { $gt: 30 } })
db.records.find({ name: /^A/ })
db.records.find({ city: "Los Angeles", status: "active" })