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Shubham Athawane
Shubham Athawane

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Beginners MongoDB Cheat-Sheet

What is MongoDB ?

MongoDB is a document-oriented NoSQL database used for high valume data storage instead of using table and rows as in the traditional relational databses, MongoDB makes use of collections and documents

Then Question arises What is documents and Collections ?

Documents : Consist of key-value pairs which are the basic unit of the data in MongoDB.

Collections : Contain sets of documents and functions which is the equivalent of relational database tables


1.Enlist available databases

β†’ Show db 
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2 . To Create a new DB

β†’ use db-name
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3 . See your current working directry

β†’  db
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4 . Delete Database

db.mydb.drop()
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5 . Create User

-> db.createUser({
    user:'admin',
    pws:'root',
    roles:["readWrite", "dbAdmin"]  
})
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6 . Creating Collections

-> db.createCollection('customers');
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7 . Showing Collections

-> show collections
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8 . Inserting values into collections

-> db.customers.insert({first_name:"shubham", last_name:"Athawane"});
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9 . View Collection Records

-> db.customers.find();
//And
-> db.customers.find().pretty();
//Note: pretty() will show you result in json formate
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10 . Add new Document in Collections

->  db.customers.insert([{"first_name":"Virat", "last_name":"Kohli"},
 {"first_name":"Taylor", "last_name":"Swift"}])
// And -> $set, $inc, $unset
-> db.customers.update({first_name:"Glen"}, {$set:{age:45}})
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11 . Rename Document

-> db.customers.update({first_name:"Virat"}, {$rename:{"age":"old"}})
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12 . Remove document

-> db.customers.remove({first_name:"Joe"})
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13 . find the matching

-> db.customers.findOne({first_name:"Joe"}) 
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14 . Count Rows

-> db.customers.count()

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15 . This is Less than/Greater than/ Less than or Eq/Greater than or Eq operators

db.customers.find({age: {$lt: 90}})
db.customers.find({age: {$lte: 90}})
db.customers.find({age: {$gt: 90}})
db.customers.find({age: {$gte: 90}})
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Discussion (2)

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capcom6 profile image
capcom6

Typo in 9: db.customers.instert must be db.customers.insert

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shubhamathawane profile image
Shubham Athawane Author

Yes! Corrected ! Thank You 😚