SQL helps us handle data with relational databases. When it comes to having different tables in a database, we need to find a way to connect the tables’ data, and this is where joins come in to save the day!

There a couple of different types of joins:

•Inner join

…

📄 Table of contents

• “this” exercise
• ‘this’ inside arrow functions
• ‘this’ in a function nested inside a method of an object
• “this” inside classes

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◉ “this” keyword in js

The JavaScript this keyword refers to the object it belongs to.

It has different values depending on where it is used:

• In a method, this…

In the near past, the web browser was much less capable than today. Every page was coming from a server.

Then the first true SPA arrived as Angular.js, brought together with all these disparate ideas in 2010. Two — way data binding, Client — side MVC, templates, and dependency injection…

One of the core advantages of react is Reusing its components and before HOC what resuability technique we are using in our development?

Most common answer is create a functional or presentational component and pass down props into it from wherever we want to use it. But isn’t this limited…

What is JwtToken (JSON Web Token) and how does it differ from an older concept of a cookie?

source: https://dev.to/techworld_with_nana/jwttoken-vs-cookie-vs-sessionid-4ndn

On Stack-Overflow I saw a couple of questions about “JwtToken vs Cookie” or “JwtToken instead of Cookie”. The fact is, JwtToken is not a direct alternative of a cookie, but…

📄 Table of contents

• definition
• basic syntax
• How can you use axios interceptors?

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Definition

Axios interceptors are functions that Axios calls for every request. You can use interceptors to transform the request before Axios sends it, or transform the response before Axios returns the response to your code. …

📄 Table of Contents

• Equality on Objects?

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Equality on objects

Two objects having the same properties and storing the same values are not equal.

{ char: 'A'} !== { char: 'A'}
//true

Detecting duplicates in arrays of objects

Let’s try out.

const arr = [{char: 'A'}, {char: 'A'}];
const set = new Set(arr);const hasDuplicates = set.size < arr.length;
console.log(hasDuplicates)
//false…

• useEffectReact Hooks — Part 2

📄 Table of Contents

• useRef
• useReducer
• useState
• useEffect
• useMemo vs useCallback
• useContext
• useQuery
• useLayoutEffect

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A key difference between class and functional components is the fact that class components have a state (stateful) while functional components are stateless.

Stateless components do not use the “this”…