In web development things that are done at the back end of the site are referred to as back-end development, Backend Development is the server side of the website where it connects like a plug data from the front end and it is called API ( Application Program Interface), the Back end includes activities like creating libraries and working with system components. It allows databases and applications to communicate with each other. Backend developers responsibility is to take care of the back-end of a website which includes the database, server, and apps, and Users can’t able to see the back-end processes, In this article, we are going to learn some of the important Back-End Developers Interview Questions And Answers For Freshers.
1. What is a callback Function In Node.Js ?
The callback Function is an Asynchronous equivalent of a function. In Node.js it makes enormous use of callbacks and triggers over them to the completion of a given task. All APIs of Node.js are written in a way that supports callbacks.
2. What is the REST API?
Application Program Interface (API ), It’s like a way between two computers which talks to each other by giving a request and getting a response the common Application Program Interface used by most mobile and web applications to talk to the server is called REST, REST stands for Representational State Transfer, Google maps uses REST API. REST API is used for a variety of purposes by interacting with the system. API developers use REST in different types of ways to develop REST APIs. At rest, we include specific actions called CRUD ( Create - Read - Update - Delete )
3. SQL and No SQL databases :
SQL is a programming language which is used for operating relational databases. SQL is a DBMS application software used to perform various tasks operations on data, There are some open-source SQL databases like MYSQL, PostgreSQL and some commercial ones like Oracle and SQL is a standard language which uses a table-based database and it’s Vertically scalable.
NO SQL is a non-relational database which does not process data in a tabular format as used in relational databases, A non-relational database encompasses a wide range of databases which can be stored in structured, unstructured and polymorphic types of data. NO SQL is also called a distributed database and it’s a declarative query language, No SQL is a document, key and graph-based database and it’s Horizontally scalable.
4. Can You Create HTTP Server In Nodejs, Explain using the sample code?
Yes, we can create an HTTP Server in Node.js. We can use the command to do so.
Sample Code:
const http = require('http');
const server = http.createServer(function (request, response)
{
response.writeHead(200, {'Content-Type': 'text/plain'});
response.end('Welcome Viewers\n');
});
server.listen(8080);
5.What Is The Global Installation Of Dependencies?
Globally installed packages/dependencies are stored in /npm directory. Such dependencies can be used in the CLI (Command Line Interface) function of any node.js, but cannot be imported using require() in the Node application directly.
Install a Node Js project globally using a -g flag as.
npm install express -g
6. What Is The Local Installation Of Dependencies?
NPM install any dependence on the local mode. A package gets installed in “node_modules' ' directory which has been present in the same folder, where the Node application has been placed.
Syntax for installing the Node JS projects locally:
npm install express
npm install --save express
Concluding With….
The above-mentioned questions are the most commonly asked Back End Interview Questions and Answers for Freshers. In our upcoming series of blogs, we will also add an advanced level of Back End Development Interview Questions and Answers to this blog that is prevalent in the Industry.
Also, read our Article:
https://blog.skillsafari.in/front-end-developer-interview-questions-and-answers-for-freshers