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MongoDB Commands that need to know each who want to work with it

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MongoDB Commands that need to know each who want to work with it

Essential MongoDB Commands Everyone Should Learn

Giriraj lodha's photo
Giriraj lodha
·

5 min read

Table of contents

There are some important commands with there example, i wish you try to implement them

List of all Databases

show databases

show dbs

Use DB or Create one if not exist

use db-name

Note :- in mongoDB DB can’t created until you can't store data in it.

View list of all collections in a DB

show collections

Command for create a collection

db.createCollection('collection-name')

Command for delete a collection

db.collection-name.drop()

Command for Delete a database

db.dropDatabase()

CRUD Operations

Create

Insert Single Document in a Collection

before continue, we need some sample data

Single Document Sample data

{
  "maker": "Boeing",
  "model": "737 Max",
  "fuel_type": "Jet Fuel",
  "engine": {
    "type": "Turbofan",
    "thrust": "23,000 lbs",
    "manufacturer": "CFM International"
  },
  "capacity": {
    "passengers": 200,
    "crew": 6
  },
  "features": [
    "In-flight Entertainment",
    "Wi-Fi Connectivity",
    "Advanced Navigation Systems"
  ],
  "wingspan": "35.9 meters",
  "cruise_speed": "839 km/h",
  "max_range": "6,570 km",
  "emergency_exit_doors": 4
}

let's insert it using the following commad

db.collection-name.insertOne(....)

use vehicles
db.createCollection.planes
db.planes.insertOne(
{
  "maker": "Boeing",
  "model": "737 Max",
  "fuel_type": "Jet Fuel",
  "engine": {
    "type": "Turbofan",
    "thrust": "23,000 lbs",
    "manufacturer": "CFM International"
  },
  "capacity": {
    "passengers": 200,
    "crew": 6
  },
  "features": [
    "In-flight Entertainment",
    "Wi-Fi Connectivity",
    "Advanced Navigation Systems"
  ],
  "wingspan": "35.9 meters",
  "cruise_speed": "839 km/h",
  "max_range": "6,570 km",
  "emergency_exit_doors": 4
}
)

ensure that you must received a acknowledged : true

Note : - when you inserting data in a collection that is not exist, created automatically, it's not necessary to create that collection manually.

Insert Many Documents at once in a Collection

Many Document [ {}, {}, {}] sample data

[
  {
    "maker": "Airbus",
    "model": "A320neo",
    "fuel_type": "Jet Fuel",
    "engine": {
      "type": "Turbofan",
      "thrust": "27,000 lbs",
      "manufacturer": "CFM International"
    },
    "capacity": {
      "passengers": 180,
      "crew": 6
    },
    "features": [
      "Wi-Fi Connectivity",
      "Advanced Avionics",
      "Fuel Efficiency"
    ],
    "wingspan": "35.8 meters",
    "cruise_speed": "870 km/h",
    "max_range": "6,300 km",
    "emergency_exit_doors": 4
  },
  {
    "maker": "Embraer",
    "model": "E195-E2",
    "fuel_type": "Jet Fuel",
    "engine": {
      "type": "Turbofan",
      "thrust": "23,000 lbs",
      "manufacturer": "Pratt & Whitney"
    },
    "capacity": {
      "passengers": 132,
      "crew": 4
    },
    "features": [
      "In-flight Entertainment",
      "Noise Reduction",
      "Optimized Fuel Consumption"
    ],
    "wingspan": "35.1 meters",
    "cruise_speed": "870 km/h",
    "max_range": "4,815 km",
    "emergency_exit_doors": 2
  },
  {
    "maker": "Bombardier",
    "model": "CRJ900",
    "fuel_type": "Jet Fuel",
    "engine": {
      "type": "Turbofan",
      "thrust": "14,510 lbs",
      "manufacturer": "General Electric"
    },
    "capacity": {
      "passengers": 90,
      "crew": 3
    },
    "features": [
      "Comfortable Seating",
      "Short-Range Efficiency",
      "Compact Design"
    ],
    "wingspan": "24.85 meters",
    "cruise_speed": "830 km/h",
    "max_range": "2,970 km",
    "emergency_exit_doors": 2
  },
  {
    "maker": "Cessna",
    "model": "Citation Longitude",
    "fuel_type": "Jet Fuel",
    "engine": {
      "type": "Turbofan",
      "thrust": "7,665 lbs",
      "manufacturer": "Honeywell"
    },
    "capacity": {
      "passengers": 12,
      "crew": 2
    },
    "features": [
      "Luxurious Interiors",
      "High-Speed Connectivity",
      "Range Efficiency"
    ],
    "wingspan": "21.0 meters",
    "cruise_speed": "882 km/h",
    "max_range": "6,482 km",
    "emergency_exit_doors": 1
  }
]

command for inset multiple documents at once

db.collection-name.insertMany(...)

db.planes.insertMany(
[
  {
    "maker": "Airbus",
    "model": "A320neo",
    "fuel_type": "Jet Fuel",
    "engine": {
      "type": "Turbofan",
      "thrust": "27,000 lbs",
      "manufacturer": "CFM International"
    },
    "capacity": {
      "passengers": 180,
      "crew": 6
    },
    "features": [
      "Wi-Fi Connectivity",
      "Advanced Avionics",
      "Fuel Efficiency"
    ],
    "wingspan": "35.8 meters",
    "cruise_speed": "870 km/h",
    "max_range": "6,300 km",
    "emergency_exit_doors": 4
  },
  {
    "maker": "Embraer",
    "model": "E195-E2",
    "fuel_type": "Jet Fuel",
    "engine": {
      "type": "Turbofan",
      "thrust": "23,000 lbs",
      "manufacturer": "Pratt & Whitney"
    },
    "capacity": {
      "passengers": 132,
      "crew": 4
    },
    "features": [
      "In-flight Entertainment",
      "Noise Reduction",
      "Optimized Fuel Consumption"
    ],
    "wingspan": "35.1 meters",
    "cruise_speed": "870 km/h",
    "max_range": "4,815 km",
    "emergency_exit_doors": 2
  },
  {
    "maker": "Bombardier",
    "model": "CRJ900",
    "fuel_type": "Jet Fuel",
    "engine": {
      "type": "Turbofan",
      "thrust": "14,510 lbs",
      "manufacturer": "General Electric"
    },
    "capacity": {
      "passengers": 90,
      "crew": 3
    },
    "features": [
      "Comfortable Seating",
      "Short-Range Efficiency",
      "Compact Design"
    ],
    "wingspan": "24.85 meters",
    "cruise_speed": "830 km/h",
    "max_range": "2,970 km",
    "emergency_exit_doors": 2
  },
  {
    "maker": "Cessna",
    "model": "Citation Longitude",
    "fuel_type": "Jet Fuel",
    "engine": {
      "type": "Turbofan",
      "thrust": "7,665 lbs",
      "manufacturer": "Honeywell"
    },
    "capacity": {
      "passengers": 12,
      "crew": 2
    },
    "features": [
      "Luxurious Interiors",
      "High-Speed Connectivity",
      "Range Efficiency"
    ],
    "wingspan": "21.0 meters",
    "cruise_speed": "882 km/h",
    "max_range": "6,482 km",
    "emergency_exit_doors": 1
  }
]
)

Read

find all data of a collection -find()

db.planes.find()

if it's not showing data in organized way you can use pretty

db.collection-name.find().pretty()

findOne()- give a data from the collection, that matched first

db.collection-name.findOne()

now if we need only specific values of a field, than use this command

db.collection-name.find({},{field-name : 1})

Don't forget to use and empty {}, and field-name : 1 ,here 1 indicate true

examples -

by default it gives _id , if you don’t want _id field than add _id : 0

db.collection-name.find({},{field-name : 1, _id : 0})

So similarly if you need any field add field-name : 1 (inside of 1 or 0 you can also add true or false)

Read results for expected values

  • for example if you want to search all “737 Max model “

      db.planes.find({model : "737 Max"})

  • you can use findOne ( remember it only return first matched result ), or any filter,

  • for example suppose i need a 737 Max model but inside whole data i just need maker and engine information

  • now if you think, how to find data based on subfield, mean if you want to find all maker with engine type Turbofan

- working on it , lets meet tomorrow

MongoDB