MERN BASIC CONCEPT And COMMAND NOTES

MERN NOTES FOR UBUNTU Operating System from Starting :

 Refference ubuntu Software : https://phoenixnap.com/kb/install-vscode-ubuntu

  Documentation: Please remove to N1,Nn..., and R1,Rn... for react and nodejs and com-dashboard and Run project one by one.

  System Requirement : 1- install npm packages, node install packages, install mongodb for database.

  Refference Resources: 

   1 - https://www.youtube.com/watch?v=zaLfOjNEOaQ&list=PL8p2I9GklV456iofeMKReMTvWLr7Ki9At

   2 - https://www.youtube.com/watch?v=EAkLuk-4KuI&list=PL8p2I9GklV456iofeMKReMTvWLr7Ki9At&index=55 (project developed this refference)

   2 - https://www.youtube.com/watch?v=PkoV-nUYhM4&list=PL8p2I9GklV456iofeMKReMTvWLr7Ki9At&index=40 (CRUD with Mongoose) 

======================MERN PROJECT 29Jan2023========================= 

 1- Create Project :

 2- npm init

 3- npm i express

 4- npm i nodemon

 5- create reactApp inside Folder: npx create-react-app xyzApp

 6- Routing in reactJs : npm i react-router-dom

   -Route depend on just above package. check version.

 7- Fixed CORS issue in Node: It must be resolve with backend using (npm install cors).

 8- What is private Component and how to create in React ? 

 9- Local storage : To keep data on browser after refresh react js page.

=============== Study Technology Planning ==================

1) React Js  - First Complete Hooks Concepts

2)  Node Js  Language - Complete Basic To A CRUD level.

3) How to remove extention of file.html in node.

4)- What is template Engine /ejs engine?

5)- This is npm package for make dynamic page.

========== Mongodb BD ============

Definations : Documents.

Commands :

0 - ...../$: mongo  

1- Show :  show dbs

2- To create db : use databaseName 

3- Create collection : db.createCollection('tblename')

4- show table : show collections.

5- delete collection : db.collectionName.drop(); 

5- delete current database : db.dropDatabase(); 

7- show collection structure : db.collectionName.find().pretty()

8- How to add one more field : db.students.update({name:},{$set:{"emp_id":"KR0047"}})

=======================================

1- How to start : 

sudo systemctl start mongod

2- How check status :

sudo systemctl status mongod

3- How to enable status : 

sudo systemctl enable mongod

4- How to stop mongodb :

sudo systemctl stop mongod

5- How to restart mongodb :

sudo systemctl restart mongod

============= CRUD Function =========

Create Operation :

 db.collectionName.insertOne() 

 db.collectionName.insertMany() 

Exam : 

db.collectionName.insertOne({

    name: "Marsh",

    age: "6 years",

    species: "Dog",

    ownerAddress: "380 W. Fir Ave",

    chipped: true

})

Read Opteration :

 db.collectionName.find()

Exam: 

db.RecordsDB.find()

 

Update Operation : 

 db.collectionName.updateOne() 

 db.collectionName.updateMany() 

 db.collectionName.replaceOne()

 Exam : db.collectionName.updateOne(

{name: "Marsh"}, 

{$set:{ownerAddress: "451 W. Coffee St. A204"}})

Delete Operation :

db.collectionName.deleteOne() 

db.collectionName.deleteMany()   

Exam :

db.collectionName.deleteOne({name:"Maki"})

 

1 - composer.json - Install to dependencies 

2 - composer.lock -  The composer. lock file prevents you from automatically getting the latest versions of your dependencies. (Range Defines)

3 - vender why not push  - Take More Time to Push time due to large file

4 - which file move on gitlab -