I am a 2021 graduate, currently working as an Analyst in an MNC. I applied for the Data Engineer-1 role at Innovaccer on June – 22, the entire process took around 3-4 weeks.
Process: Online Test, Technical Interview, HR Interview
Round 1(Online Test): The online test was conducted on the Hackerrank portal and comprised 6 questions in total. 5 of them are SQL queries and one subjective question based on Git. SQL queries ranged from easy to hard, where 2 of them were easy-medium, 1 of moderate difficulty, and the remaining 2 could be categorized as hard. with 6 questions in total. 5 SQL and 1 Subjective
- Return Name in uppercase satisfying the given condition
- Return data of students who scored more than the average marks
- From the given table, return the total count of different severity of Covid among the three age groups, where age groups from the given data were supposed to be created by me using SQL functionalities.
- From the given data of 3 tables location, companies, and employees, find out the location with most companies and return the name and company of employees who work in that location
- A question where the top 3 records in each category were to be fetched with some other conditions applied (I used Window Functions here). This one had a trick to sorting where I used another Window function to extract an additional column to sort on to get the desired result.
- Subjective question based on various commands in Git with an explanation.
Round 2(Technical Interview): The interview was conducted on google meets and was scheduled for 1 hour. The interview started with the infamous “Tell me something about yourself” question, followed by a thorough discussion of my current role and the tools and technologies used. Moving on the interviewer asked me below mentioned questions:
1. A table of 4 columns contains duplicate rows. How to extract the duplicate rows?
Solution: I explained it using 4 ways:
- Using GROUP BY
- Using SELF JOIN
- Using DISTINCT keywords
- Using Windows Function (ROW_NUMBER in this case)
2. Two tables A and B have one column “Id” (duplicates allowed), what would be the result of the inner join of these two?
- What would be the result if table A contains Null values as well?
- How to achieve the same result as in inner join using left join?
- Use right join but the result set must not include the matching rows?
Note: For getting an idea of the above-mentioned question one can refer to https://youtu.be/xR87ctOgpAE
3. How to delete duplicates from a SQL table?
Solution: https://www.mysqltutorial.org/mysql-delete-duplicate-rows/
4. Given a table with StudentId, Marks, and SubjectName, find the details of a student with the subject in which they scored lowest each student?
Solution: Used Windows Function (RANK).
Follow-up question: What would you do if marks are equal in two subjects? How to return only one row in that case with a subject that comes first lexicographically?
Solution: Used another Window function ROW_NUMBER and fetched only the queries where row number and rank is 1.
5. Questions related to the project and basics of Python data structures and libraries like Pandas and NumPy.
6. COALESCE Function? Explanation and Use?
Round 3(HR Round): This round revolved around general discussion on my current job role, work culture at Innovaccer, why am I looking for a switch, Why Innovaccer, what I know about Innovaccer, etc.
Verdict: Selected
Tips: Be honest and confident while answering the questions, trust me, you have it in you.
I would like to thank geeks for geeks to help me with the preparation of core subjects concepts and puzzles. It is indeed a one-stop solution for Software Field Students.