Hi everyone,

I interviewed with Amazon a couple of weeks ago for a Data Engineer role requiring 1+ years of experience. I wanted to share my interview experience in case it helps others prepare.

Round 0: Technical Assessment
This was a 90-minute online assessment consisting of:

• 10 MCQs
• 2 medium-level SQL questions

The SQL questions were focused on query-writing skills and required a good understanding of SQL fundamentals.

Round 1: Technical Interview (Elimination Round)

Topics Covered: ETL workflow design
Database concepts and architecture

The interview started with a brief introduction and a discussion about my resume. Since I had mentioned Apache Spark, the interviewer immediately asked questions related to Spark joins and data processing concepts.
Questions Asked:

• Difference between: Physical Joins, Hash Join, Broadcast Nested Loop Join

• Difference between GROUP BY and Window Functions

• Explain Slowly Changing Dimensions (SCD Types)

• Difference between Star Schema and Snowflake Schema

• How do you optimize SQL queries?

• Difference between: Data Warehouse, Data Lake, Lakehouse

• Difference between traditional batch architecture and event-driven incremental ingestion

• Questions related to Idempotency

• Questions related to Change Data Capture (CDC)

SQL Question
At the end, I was given a live SQL coding problem on consecutive user logins.

Read and understand every concept thoroughly. Make sure your fundamentals are crystal clear, especially around SQL, ETL, data warehousing concepts.

All the best !