I have applied via Linkedin and received call from HR.
There are 4 rounds of interview.
Normally, We see machine coding as first round, due to the unavailability of slots, I had machine coding as second round.
Round 1(Data Modelling + SQL Queries): I was asked to create data model for an e-commerce company.
- Need to explain each table and relation between them in an optimized way.
- Then, asked 3 SQL queries ( difficulty level-medium to hard).
Tips: Prepare well for data modeling and practice hard SQL queries.
Round 2(Machine Coding): I was given few json documents and asked to provide solutions to the given queries. (free to use any language/environment).
- I used spark to solve them. It was my first time dealing with json format, so I struggled a bit in this round.
- Panel members were satisfied with my approach and logic.
Tips: Be familiar with all file formats before this round and play with dataframes if you use spark.
Round 3(Tech Round): I have explained my project end to end and few follow-up questions on the same.
Then, asked about
- Spark internals and optimization techniques in spark (in-depth)
- Why no-sql databases( advantages)
- Few questions related to big data stuff.
- 2 DSA questions based on the array(similar to missing number) (difficulty level- medium)
- Again questions on spark internals based on jobs, stages, tasks.
- Given one ETL scenario and asked to explain end-to-end flow from ingestion till data warehouse. Few SQL queries based on the same scenario. The interviewer was satisfied with my approach.
Tips:
- Understand spark internals, optimization techniques thoroughly as this round has high weightage and thereby it gives confidence to the interviewer that you can handle work in spark environment.
- Prepare for DSA questions ( you never know that you may face Hard questions)
Cleared this round and have to face final round.
Round 4(HM Round): This round will test your project understandings( end to end).
- Lot of follow up questions on every answer you say.
- Be ready to face questions on each part of your project.
Tips: Question yourself on each part of your project( How and Why) before facing HM round.
Verdict: Selected.