Me postulé en línea. Acudí a una entrevista en Blackstraw (Chennai) en dic 2024
Entrevista
First Round was taken by HR. He asked me few questions about myself, project and asked a couple of technical questions as an initial screening. It was followed by 2 technical rounds.
HR : M*h*rz*d
Technical1: S**t**
Technical2: M*h*m*d D*w**d*
Preguntas de entrevista [1]
Pregunta 1
1. What are the differences between snowflake schema and star schema?
2. Get the nth highest salary in each department from employee table. Was asked to write the sol in both SQL and PySpark
3. Write the python program for fibonacci series
4. What happens when you submit a job to spark ?
5. What is DAG?
6. What is the difference between Stages & Task in spark?
7. Can Stage and Task run in parallel?
8. Identify whether the given operations [select, filter, join, group by] are
transformation or action ?
9. How do you implement incremental data loading?
10. Given 2 tables, each table has single column ID, get the values that are present in table B but not in table A.
tableA [ ID : 1 2 3 4 5]
tableB [ ID : 4 5 6 7]
Expected Output : [6 7]
11. Pyspark coding question on split and explode functions.
Me postulé en persona. Acudí a una entrevista en Blackstraw (Pallāvaram) en abr 2026
Entrevista
I attended a walk‑in interview at BlackStraw. The process had three rounds:
Round 1 – HR Intro
Self‑introduction.
Questions from my resume.
Reason for leaving previous company.
Do you have any other offers?
Round 2 – Technical Round
Self‑introduction.
What is SCD (Slowly Changing Dimension) and its types?
Which type of join would you use if one table is large and the other is small?
How will you increase the performance of a query in SQL or PySpark?
Difference between repartition and coalesce in PySpark.
What is incremental data loading?
How do you implement incremental data loading?
What are the types of transformers?
Difference between view and materialized view
Round 3 – Managerial HR Round
Self‑introduction.
General discussion about background, expectations, and cultural fit.
Do you have any other offers?
Preguntas de entrevista [1]
Pregunta 1
Round 1 – HR Intro
Self‑introduction.
Questions from my resume.
Reason for leaving previous company.
Do you have any other offers?
Round 2 – Technical Round
Self‑introduction.
What is SCD (Slowly Changing Dimension) and its types?
Which type of join would you use if one table is large and the other is small?
How will you increase the performance of a query in SQL or PySpark?
Difference between repartition and coalesce in PySpark.
What is incremental data loading?
How do you implement incremental data loading?
What are the types of transformers?
Difference between view and materialized view
Round 3 – Managerial HR Round
Self‑introduction.
General discussion about background, expectations, and cultural fit.
Do you have any other offers?