Rainbow Papers Interview Questions and Answers

React lifecycle, Fragment vs React.Fragment, React.PureComponent

• React lifecycle consists of mounting, updating, and unmounting phases

• Fragment is a shorthand for React.Fragment, used to group multiple elements

• React.PureComponent is a class component that implements shouldComponentUpdate method for performance optimization

JavaScript hoisting and differences between let, var and const.

• Hoisting is a JavaScript mechanism where variables and function declarations are moved to the top of their scope.

• Var declarations are hoisted to the top of their scope, while let and const declarations are not.

• Var can be redeclared and reassigned, let can be reassigned but not redeclared, and const cannot be reassigned or redeclared.

• Using const is recommend...read more

Prevent rerendering of a child component in React

• Use shouldComponentUpdate() lifecycle method

• Use React.memo() to memoize functional components

• Use PureComponent instead of Component

• Pass props as a callback function to avoid unnecessary re-renders

• Use React.PureComponent for class components

• Use React.memo() for functional components

Code to find common elements between two arrays

• Iterate through each element of the first array

• Check if the element exists in the second array

• If yes, add it to a new array or print it

Query to delete duplicate rows in a table

• Use GROUP BY clause to group the rows by their unique values

• Use HAVING clause to filter out the groups with count greater than 1

• Use DELETE statement to delete the duplicate rows

Spring IOC is a container that manages the lifecycle of Java objects. Dependency Injection is a design pattern that allows objects to be loosely coupled.

• Spring IOC is a container that manages the creation and destruction of objects

• Dependency Injection is a design pattern that allows objects to be loosely coupled

• Spring IOC uses Dependency Injection to inject dependencies into objects

• Dependency Injection can be implement

Defects in welding section can include porosity, lack of fusion, undercutting, and distortion.

• Porosity: Formation of small cavities or voids in the weld metal due to trapped gas.

• Lack of fusion: Incomplete bonding between the weld metal and base metal.

• Undercutting: Formation of groove-like depressions along the edges of the weld due to excessive heat or incorrect technique.

• Distortion: Deformation or warping of the welde

No, the company does not impose absences for an employee's marriage leave.

• Marriage leave is usually a part of an employee's entitled leave balance.

• The company may require prior notice and documentation for the leave.

• The employee may also be required to complete pending work before taking the leave.

• The company may have policies regarding the duration and frequency of marriage leave.

• The employee may also be eligible for ...read more

Identify alternative channels and explore new opportunities to reach the target market.

• Conduct market research to identify potential alternative channels

• Explore digital marketing options such as social media, email marketing, and online advertising

• Partner with complementary businesses to reach a wider audience

• Attend industry events and conferences to network and generate leads

• Consider creating a new channel or distribu...read more