Ethiraj Associates Interview Questions and Answers

Windows function in SQL is used to perform calculations across a set of rows that are related to the current row.

• Windows functions are used to calculate values based on a group of rows

• They are used with the OVER clause

• Examples include ROW_NUMBER(), RANK(), DENSE_RANK(), SUM(), AVG(), MIN(), MAX()

Coalesce reduces the number of partitions in a DataFrame, while repartition increases the number of partitions.

• Coalesce is used to reduce the number of partitions in a DataFrame without shuffling the data

• Repartition is used to increase the number of partitions in a DataFrame and can involve shuffling the data

• Coalesce is more efficient than repartition when reducing partitions as it avoids shuffling

React Js allows for efficient and reusable UI components, virtual DOM for faster rendering, and easy integration with other libraries.

• Efficient and reusable UI components make development faster and easier.

• Virtual DOM allows for faster rendering by only updating the parts of the DOM that have changed.

• Easy integration with other libraries like Redux for state management.

• React Native allows for building mobile apps using