#join

What is the difference between narrow and wide transformations in Apache Spark? Explain with examples.

Explain the differences between Repartition and Coalesce. When would you use each?

What is the difference between partitioning and bucketing in Spark, and when would you use bucketing?

What strategies can you use to handle skewed data in Spark?

Describe a time when you had to optimize a slow SQL query. What steps did you take?

Explain the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN.

How do you handle NULL values in SQL? Mention functions like COALESCE and NULLIF.

Write a Python function to check if a string is a palindrome.

Describe a scenario where partitioning and bucketing would improve query performance.

When would you choose a Snowflake schema over a Star schema?

Explain the concept of Broadcast Join in Spark. When should it be used?

What challenges did you face, and how did you tackle them?

Why do you want to join this company?

What is the difference between SQL and NoSQL databases?

Detail examples of inner, outer, left, and right joins.

Explain SQL Window Functions with examples.

Explain the use of the MERGE statement in SQL.

How do you handle NULL values in SQL? Mention functions like COALESCE and ISNULL.

What are primary keys and foreign keys? Why are they important?

What is a self-join, and when would you use it?