Switchon Software Developer Interview Questions and Answers

React Queries are a library for managing server state in React applications.

• React Queries provide a way to fetch and cache data from an API in React components.

• They offer features like caching, background fetching, and automatic refetching.

• React Queries can handle complex data fetching requirements, such as pagination and infinite scrolling.

Yes, useEffect() hook can run twice under certain conditions.

• useEffect() hook can run twice if the dependencies array changes between renders.

• This can happen if the dependencies array contains values that change frequently.

• For example, if a state variable is included in the dependencies array and it is updated in the component, useEffect() will run again.

Joins in SQL are used to combine rows from two or more tables based on a related column between them.

• Joins are used to retrieve data from multiple tables based on a related column between them

• Types of joins include INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN

• INNER JOIN returns rows when there is at least one match in both tables

• LEFT JOIN returns all rows from the left table and the matched rows from the right table

• ...read more

Objects are instances of classes in OOPs. Classes are blueprints for creating objects with attributes and methods.

• Objects are instances of classes

• Classes are blueprints for creating objects

• Classes define attributes and methods for objects

• Example: Class 'Car' with attributes like 'color' and methods like 'drive'