Telephonic Round

• General questions about data structures (difference between HashSet, ArrayList, and HashMap), questions about HTTP services and protocols, and databases (INNER JOIN and OUTER JOIN).
• Questions about your past projects and experience.

On-site Rounds

1st Round: This was a technical round. The interviewer asked a couple of programming and design questions.

2nd Round: This was a behavioral round. They asked about past projects and experience in detail.

1. Given a number in the form of a string, return a single-digit sum of the given number.

For example: 12345 -> 15 -> 6. You have to return 6.

Explanation: Continuously sum the digits until you get a single digit. Given number sum will be 15 (it is still in double digits). Then sum it again: 6. We just return 6.

1. You have a JSON of books and libraries, and you have to design the database tables.

2. SQL query about inner join with group by.